Research
Yohimbine HCl (Standardized)
98 peer-reviewed studies curated from PubMed and Semantic Scholar.
Studies
Sorted by quality and recency
Yohimbine as a pharmacological probe for alcohol research: a systematic review of rodent and human studies.
Systematic review of rodent and human studies using yohimbine as a pharmacological probe in alcohol research. The review identifies 67 studies, highlighting yohimbine's role in evaluating noradrenergic activation and its potential as a translational tool, though limited by human study findings and sex differences in mechanistic actions.
The effects of yohimbine and hydrocortisone on selective attention to fearful faces: An fMRI study.
RCT investigating the effects of yohimbine and hydrocortisone on selective attention to fearful faces using an fMRI scanner. The study found an attentional bias toward fearful faces across all groups with related neuronal activation in the left cuneus, but no significant differences between treatment groups.
Effects of stress-related neuromodulators on amygdala and hippocampus resting state functional connectivity.
RCT with 165 participants investigating the influence of yohimbine and hydrocortisone on amygdala and hippocampal resting state functional connectivity. The combination of yohimbine and hydrocortisone increased RSFC between the amygdala, hippocampus, and cerebellum compared to placebo, suggesting a role in the human stress response. No differences were found when each substance was administered alone.
No changes in triple network engagement following (combined) noradrenergic and glucocorticoid stimulation in healthy men.
Double-blind, placebo-controlled study with 165 healthy males administering 10mg oral yohimbine and/or 10mg oral hydrocortisone before resting state scanning. No changes were found in within-network connectivity of salience-, executive control-, and default mode networks, supporting the null hypothesis.
The effects of hydrocortisone and yohimbine on human behavior in approach-avoidance conflicts.
RCT investigating the effects of hydrocortisone and yohimbine on approach-avoidance conflict behavior in 96 healthy individuals. Yohimbine affected risky foraging latency under predation, but no main effect of hydrocortisone or their interaction on behavior was found. Gender differences were observed, potentially due to endogenous testosterone levels.
Alpha-2 Adrenoreceptor Antagonist Yohimbine Potentiates Consolidation of Conditioned Fear.
RCT investigating the effects of yohimbine and sulpiride on long-term fear conditioning and extinction in 51 healthy male students. Yohimbine treatment enhanced fear recall, indicated by increased salivary alpha-amylase activity and electrophysiological measures, suggesting potentiation of fear memory consolidation.
Effects of hydrocortisone and yohimbine on selective attention to emotional cues.
RCT with 104 healthy men examining the effects of yohimbine and hydrocortisone on selective attention to emotional facial cues. Yohimbine and hydrocortisone interaction affected attention to sad faces, with hydrocortisone alone causing an attentional bias away from sad faces.
Noradrenergic system and cognitive flexibility: Disentangling the effects of depression and childhood trauma.
Double-blind placebo-controlled study investigating the effect of yohimbine on cognitive flexibility in MDD patients with and without adverse childhood experiences. Yohimbine administration had no effect on task switching performance.
(Lack of) Effects of noradrenergic stimulation on human working memory performance.
RCT assessing dose-dependent effects of yohimbine on working memory performance in 121 healthy humans using an adaptive n-back task. No significant effects of yohimbine on working memory were found, with Bayesian analyses supporting the absence of an association.
Effects of hydrocortisone and yohimbine on decision-making under risk.
RCT with 104 healthy young men investigating the effects of yohimbine and hydrocortisone on risky decision-making in a gambling task. Hydrocortisone reduced risky choices in gain-only trials, while yohimbine had no effect. Loss aversion was unaffected by either substance.
Single-dose and steady-state pharmacokinetics of clomipramine, yohimbine and clomipramine/yohimbine combination: A clinical drug-drug interaction study.
Pharmacokinetic study of clomipramine and yohimbine, investigating drug-drug interactions in 15 healthy male subjects. The study found a clinically significant interaction for multiple dosing of yohimbine in combination with clomipramine, likely due to competitive inhibition of yohimbine metabolism by clomipramine.
Effects of Acute Yohimbine Hydrochloride Supplementation on Repeated Supramaximal Sprint Performance.
This study examined the effects of a single acute dose of yohimbine hydrochloride on repeated anaerobic sprint ability in 18 physically active females. Results showed that yohimbine hydrochloride supplementation significantly increased mean power, total work, and heart rate, while reducing fatigue index and post-exercise lactate levels compared to placebo. Yohimbine hydrochloride also resulted in higher epinephrine concentrations, suggesting ergogenic benefits for sprint performance.
Oral Yohimbine as a New Probe Drug to Predict CYP2D6 Activity: Results of a Fixed-Sequence Phase I Trial.
This phase I trial investigated the pharmacokinetics of yohimbine in relation to CYP2D6 genotypes in 16 healthy volunteers. The study found that yohimbine clearance was highly variable and dependent on CYP2D6 genotype, with paroxetine significantly reducing clearance in extensive metabolisers. Yohimbine did not affect CYP3A activity, suggesting its potential as a probe drug for predicting CYP2D6 activity.
Cortisol reactivity and situational drug use in cocaine-dependent females.
Double-blind study on cocaine-dependent women assessing cortisol reactivity to cue-reactivity tasks after administration of yohimbine or placebo. Results indicated significant responses across all subscales of the Inventory of Drug Taking Situations during yohimbine administration, suggesting an association between situational and physiological risk factors.
Enhancement of exposure therapy in participants with specific phobia: A randomized controlled trial comparing yohimbine, propranolol and placebo.
RCT comparing virtual reality exposure therapy (VRET) with yohimbine, propranolol, and placebo in 56 participants with specific phobia. No significant differences were found between the groups, suggesting no enhancement of VRET by yohimbine or propranolol.
Comparison of Atipamezole with Yohimbine for Antagonism of Xylazine in Mice Anesthetized with Ketamine and Xylazine.
This study is a single-dose crossover comparison of atipamezole and yohimbine for reversing xylazine-ketamine anesthesia in mice. Mice recovered more rapidly with atipamezole compared to yohimbine and saline, indicating atipamezole's greater effectiveness at the doses evaluated.
Noradrenergic Stimulation Impairs Memory Generalization in Women.
Double-blind, placebo-controlled study testing the effects of yohimbine and hydrocortisone on memory generalization in healthy men and women. Yohimbine led to a significant impairment in memory generalization in women, but not in men, while hydrocortisone had no effect.
Influence of the noradrenergic system on the formation of intrusive memories in women: an experimental approach with a trauma film paradigm.
Experimental, double-blind, placebo-controlled study in 118 healthy women assessing the influence of noradrenergic system activity on intrusive memories. Participants received yohimbine, clonidine, or placebo before watching a trauma film. Yohimbine delayed the decrease of intrusions and their vividness, and increased salivary cortisol levels during the film.
Effects of yohimbine and drug cues on impulsivity and attention in cocaine-dependent men and women and sex-matched controls.
Double-blind placebo-controlled cross-over study examining the effects of yohimbine and cocaine cues on executive function in cocaine-dependent men and women and sex-matched controls. Healthy controls showed increased commission errors under yohimbine, while cocaine-dependent individuals showed decreased omission errors. Significant sex differences were observed in omission errors and hit reaction times.
Yohimbine administration and cue-reactivity in cocaine-dependent individuals.
Double-blind placebo-controlled cross-over study examining the effects of yohimbine on subjective, endocrine, and physiological responses to cocaine cues in cocaine-dependent individuals. Yohimbine increased anxiety, craving, salivary cortisol, and dehydroepiandrosterone levels, with more pronounced effects in women.
Genotype-based treatment of type 2 diabetes with an α2A-adrenergic receptor antagonist.
RCT of 50 type 2 diabetes patients based on ADRA2A genotype, testing the α(2A)AR antagonist yohimbine. Patients with the risk variant had lower insulin secretion, which was improved by 29% after 20 mg yohimbine administration, aligning secretion levels with low-risk allele carriers.
Does yohimbine hydrochloride facilitate fear extinction in virtual reality treatment of fear of flying? A randomized placebo-controlled trial.
RCT examining the effects of yohimbine hydrochloride (YOH) on fear extinction in virtual reality treatment for fear of flying. Sixty-seven participants were randomized to receive YOH or placebo before virtual reality exposure therapy. Both groups showed significant anxiety reduction, but YOH did not enhance outcomes.
Stimulation of the noradrenergic system during memory formation impairs extinction learning but not the disruption of reconsolidation.
The study investigated the effects of yohimbine HCl, an α(2)-adrenergic receptor antagonist, on fear memory consolidation and extinction learning using a differential fear conditioning procedure. Yohimbine was administered before memory acquisition, and propranolol HCl, a β-adrenergic receptor antagonist, was used to manipulate reconsolidation. The findings suggest that noradrenergic strengthening of fear memory impairs extinction learning but does not affect the disruption of reconsolidation.
The relationship between resting blood pressure and acute pain sensitivity: effects of chronic pain and alpha-2 adrenergic blockade.
This study tested the effects of alpha-2 adrenergic blockade with yohimbine on the relationship between resting blood pressure and acute pain sensitivity in 32 healthy controls and 24 chronic low back pain participants. The study found significant hyperalgesic effects of yohimbine in chronic pain participants with lower systolic blood pressures, but not in those with higher pressures or in controls. Results suggest blood pressure-related hypoalgesia can occur even when alpha-2 adrenergic systems are blocked.
Noradrenergic stimulation enhances human action monitoring.
RCT examining the effect of yohimbine, a selective alpha2-adrenoceptor antagonist, on human action monitoring. Yohimbine increased the amplitude of error-related negativity and reduced action errors, suggesting a specific effect on action monitoring.
Acute yohimbine increases laboratory-measured impulsivity in normal subjects.
RCT examining the effects of yohimbine on impulsivity in healthy subjects. Yohimbine increased impulsive IMT commission errors by over 50% at higher doses, suggesting increased impulsivity possibly related to increased norepinephrine.
Addition of the alpha2-antagonist yohimbine to fluoxetine: effects on rate of antidepressant response.
A randomized double-blind controlled trial tested the combination of yohimbine with fluoxetine in 50 subjects with major depressive disorder. The addition of yohimbine to fluoxetine resulted in a more rapid onset of antidepressant action and a higher percentage of responders compared to fluoxetine alone over a 6-week period.
Sympathetically mediated hypertension in autonomic failure.
The study investigated the effect of oral yohimbine on seated systolic blood pressure in patients with multiple system atrophy (MSA) or pure autonomic failure (PAF). The SBP response to yohimbine was greater in MSA patients compared to PAF patients. Residual sympathetic activity was found to drive supine hypertension in MSA.
Yohimbine for erectile dysfunction: a systematic review and meta-analysis of randomized clinical trials.
Systematic review and meta-analysis of randomized, placebo-controlled trials of yohimbine monotherapy for erectile dysfunction. The meta-analysis demonstrated that yohimbine is superior to placebo in treating erectile dysfunction, with serious adverse reactions being infrequent and reversible.
Clinical guidelines panel on erectile dysfunction: summary report on the treatment of organic erectile dysfunction. The American Urological Association.
The American Urological Association's Clinical Guidelines Panel analyzed literature on treatments for organic erectile dysfunction, including yohimbine. The meta-analysis found yohimbine to have marginal efficacy for erectile dysfunction, and it is not recommended for standard patients.
Augmenting treatment efficiency in exposure therapy for PTSD: a randomized double-blind placebo-controlled trial of yohimbine HCl.
A double-blind placebo-controlled randomized trial piloted yohimbine augmentation in 26 males with combat-related PTSD. Yohimbine led to higher arousal during the drug/exposure visit and lower trauma-cued heart-rate reactivity one week later. It also resulted in greater between-session habituation and more rapid improvement on depression over the course of care.
Pharmacological stress impairs working memory performance and attenuates dorsolateral prefrontal cortex glutamate modulation.
This study used a double-blind, randomized crossover design to assess the effects of acute stress induced by yohimbine and hydrocortisone on working memory performance and dorsolateral prefrontal cortex glutamate modulation. Results showed that acute stress significantly impaired working memory performance and attenuated glutamate modulation compared to placebo.
Combined Effects of Glucocorticoid and Noradrenergic Activity on Loss Aversion.
Double-blind, placebo-controlled study investigating the effects of yohimbine and hydrocortisone on loss aversion during financial decision making in healthy young men. The combination of both drugs reduced loss aversion without affecting risk attitude or choice consistency.
Attention bias dynamics and symptom severity during and following CBT for social anxiety disorder.
RCT examining the relation between attention bias and social anxiety symptom severity during yohimbine- or placebo-augmented CBT in adults with social anxiety disorder. Attention bias toward threat and temporal variability in attention bias reduced over the course of CBT, but no causal relation was found between attentional dysregulation and symptom severity reduction.
Enhancing exposure therapy for PTSD with yohimbine HCL: protocol for a double-blind, randomized controlled study implementing subjective and objective measures of treatment outcome.
The study is a double-blind, randomized controlled trial investigating the effect of yohimbine HCL on enhancing exposure therapy outcomes for veterans with PTSD. It involves a single administration of yohimbine HCL paired with the first session of imaginal exposure in 40 veterans, measuring both psychological and psychophysiological outcomes.
Yohimbine enhancement of exposure therapy for social anxiety disorder: a randomized controlled trial.
RCT of 40 adults with social anxiety disorder comparing yohimbine HCl (10.8 mg) to placebo as an augmentation to exposure therapy. Yohimbine resulted in faster improvement and better outcomes on self-report measures of social anxiety and depressed mood severity, but not on clinician-rated measures.
Norepinephrine and impulsivity: effects of acute yohimbine.
RCT assessing the effects of yohimbine on norepinephrine release, blood pressure, and impulsivity in 23 healthy controls. Yohimbine increased plasma catecholamine metabolites, blood pressure, and impulsive errors on a continuous performance test.
Effects of noradrenergic stimulation on memory in patients with major depressive disorder.
Placebo-controlled crossover study of 20 patients with MDD and 18 healthy controls receiving 5 mg yohimbine to test memory function. Yohimbine improved memory consolidation, especially in depressed patients, but did not affect memory retrieval or working memory.
Synergistic effect of norepinephrine transporter blockade and α-2 antagonism on blood pressure in autonomic failure.
Single-blind, crossover RCT with 17 patients with autonomic failure testing the effects of yohimbine, atomoxetine, and their combination on blood pressure and orthostatic tolerance. The combination significantly increased seated systolic blood pressure and orthostatic tolerance compared to placebo, suggesting a synergistic effect.
Yohimbine increases opioid-seeking behavior in heroin-dependent, buprenorphine-maintained individuals.
This clinical study tested whether yohimbine increases opioid-seeking behavior in heroin-dependent, buprenorphine-stabilized volunteers. Yohimbine significantly increased hydromorphone demand inelasticity and produced modest increases in blood pressure and opioid withdrawal symptoms, without significant subjective distress or elevated craving.
Effect of yohimbine on detomidine induced changes in behavior, cardiac and blood parameters in the horse.
Randomized crossover study in nine healthy adult horses examining the effects of yohimbine on detomidine-induced changes. Yohimbine rapidly reversed detomidine-induced sedation, bradycardia, atrio-ventricular heart block, and hyperglycemia.
The effects of yohimbine on the pharmacokinetic parameters of detomidine in the horse.
Randomized crossover study in nine healthy adult horses to describe the pharmacokinetics of detomidine and yohimbine when administered in combination. Yohimbine plasma concentrations increased significantly when administered after detomidine, affecting its clearance and volume of distribution.
Avoidant coping in panic disorder: a yohimbine biological challenge study.
Double-blind, placebo-controlled study involving 42 individuals, including 20 healthy controls and 22 patients with panic disorder, to assess the effects of yohimbine on panic symptoms. Patients with panic disorder who used avoidance-oriented coping strategies reported increased severity in panic symptoms during the yohimbine challenge compared to placebo.
Psychological and neuroendocrine responses to social stress and to the administration of the alpha-2-receptor antagonist, yohimbine, in highly trained endurance athletes in comparison to untrained healthy controls.
RCT comparing psychological and neuroendocrine responses to yohimbine and psychosocial stress in 12 male athletes and 12 untrained male controls. Both yohimbine and stress increased anxiety symptoms, plasma cortisol, heart rate, and blood pressure, with no significant differences between athletes and controls.
Comparative efficacy of yohimbine against pyridostigmine for the treatment of orthostatic hypotension in autonomic failure.
This study compared the efficacy of yohimbine and pyridostigmine in treating orthostatic hypotension in patients with autonomic failure. Yohimbine significantly improved standing diastolic blood pressure and presyncopal symptoms compared to placebo, while pyridostigmine did not. No synergistic effect was found when combining both drugs.
Effect of the α(2)-adrenoceptor antagonist yohimbine on vascular regulation of the middle cerebral artery and the ophthalmic artery in healthy subjects.
This randomized, double-masked, placebo-controlled study investigated the effect of yohimbine on vascular regulation in healthy male volunteers. Yohimbine significantly shortened the time for ophthalmic artery blood velocities to return to baseline after a step decrease in blood pressure, suggesting a role for α2-adrenoceptors in the vasoconstrictor response of vasculatures distal to the ophthalmic artery.
Effects of yohimbine and hydrocortisone on panic symptoms, autonomic responses, and attention to threat in healthy adults.
RCT examining the effects of yohimbine, hydrocortisone, and their combination on panic symptoms and attention to threat in 32 healthy adults. Yohimbine and the combination increased panic symptoms, with yohimbine alone having a greater effect. Yohimbine reduced attention bias to angry faces, suggesting modulation of attention under stress.
Facilitation of fear extinction in phobic participants with a novel cognitive enhancer: a randomized placebo controlled trial of yohimbine augmentation.
RCT examining the effect of yohimbine hydrochloride on fear extinction in claustrophobic participants. Participants received 10.8mg yohimbine or placebo before exposure sessions. Yohimbine group showed significantly greater improvement in peak fear at one-week follow-up.
Relationship of cytochrome P450 pharmacogenetics to the effects of yohimbine on gastrointestinal transit and catecholamines in healthy subjects.
RCT of 30 healthy volunteers randomized to yohimbine or placebo for 7 days, assessing gastrointestinal transit, haemodynamics, and plasma catecholamines. Yohimbine increased diastolic blood pressure and plasma noradrenaline but did not affect gastrointestinal transit. CYP2D6 and CYP3A4 genotypes influenced yohimbine's effects on sympathetic and gastrointestinal systems.
Yohimbine in the treatment of orgasmic dysfunction.
RCT studying the effect of yohimbine in 29 men with orgasmic dysfunction. Patients were given a 20-mg dose of yohimbine, with dose titration allowed at home. Of the 29 patients, 16 managed to reach orgasm and ejaculate, with additional patients achieving orgasm with a vibrator. Yohimbine was found to be a useful treatment option for orgasmic dysfunction.
Antagonistic effects of yohimbine in pigs anaesthetised with tiletamine/zolazepam and xylazine.
RCT in 12 pigs comparing the effects of yohimbine following tiletamine/zolazepam and xylazine anesthesia. Yohimbine reduced immobilization and analgesia scores, rectal temperature, and glucose concentration, and improved recovery times compared to control.
Yohimbine attenuates baroreflex-mediated bradycardia in humans.
RCT in 10 healthy men testing the effect of yohimbine on baroreflex-mediated bradycardia. Yohimbine increased heart rate and blood pressure, and decreased baroreflex control of heart rate, possibly through parasympathetic mechanisms.
Yohimbine: the effects on body composition and exercise performance in soccer players.
RCT of 20 top-level male soccer players assessing yohimbine supplementation effects on body composition and exercise performance. Yohimbine significantly reduced body fat percentage but did not alter body mass, muscle mass, or performance indicators. No side effects were reported.
Salivary alpha-amylase levels after yohimbine challenge in healthy men.
Randomized double-blind placebo-controlled study assessing cardiovascular effects and salivary alpha-amylase (sAA) and catecholamine secretion after iv injection of yohimbine in 13 healthy males. Yohimbine increased sAA activity, blood pressure, salivary flow rate, and catecholamines compared to placebo, suggesting sAA might be an indirect indicator of the central sympathetic system.
[Individualising the evidence--single case randomized trial].
A single case randomized trial was conducted on a 64-year-old patient with essential hypertension to assess the efficacy of oral yohimbine for erectile dysfunction. The results of 10 comparisons between placebo and yohimbine revealed no difference, indicating no significant effect of yohimbine on erectile dysfunction in this case.
The illusion of mental health: in the mind of which beholder?
The study involved administering yohimbine, an alpha-sub-2-adrenoreceptor antagonist, to 36 children with anxiety disorders to assess neuroendocrine reactions. Findings suggest that self-reported anxiety may align more closely with anxiotypic neuroendocrine profiles than clinician ratings in some cases.
An oral yohimbine/L-arginine combination (NMI 861) for the treatment of male erectile dysfunction: a pharmacokinetic, pharmacodynamic and interaction study with intravenous nitroglycerine in healthy male subjects.
Two placebo-controlled, randomized, double-blind, crossover studies assessed the pharmacokinetics and pharmacodynamics of NMI 861, a combination of yohimbine and L-arginine, in healthy male subjects. NMI 861 was well tolerated with no significant adverse reactions and showed no significant hypotensive interaction with intravenous nitroglycerine.
Clonidine and yohimbine in opioid-dependent humans responding under a naloxone novel-response discrimination procedure.
The study investigated the effects of naloxone, yohimbine, and clonidine in opioid-dependent humans using a drug discrimination procedure. Naloxone and yohimbine influenced naloxone- and 'novel'-appropriate responding, while clonidine produced primarily placebo-appropriate responding. Clonidine partially attenuated naloxone-occasioned responding and some naloxone-induced changes in self-report measures.
Efficacy and safety of a novel combination of L-arginine glutamate and yohimbine hydrochloride: a new oral therapy for erectile dysfunction.
Double-blind, placebo-controlled, three-way crossover RCT comparing the efficacy and safety of L-arginine glutamate and yohimbine hydrochloride combination to yohimbine alone and placebo in 45 patients with erectile dysfunction. The combination significantly improved Erectile Function Domain scores compared to placebo, particularly in patients with mild to moderate ED.
Yohimbine treatment of organic erectile dysfunction in a dose-escalation trial.
RCT evaluating yohimbine treatment in 18 nonsmoking men with organic erectile dysfunction. Yohimbine improved erectile function in 50% of participants, particularly those with less severe dysfunction, as indicated by increased rigidity and higher sexual health scores.
Yohimbine-induced withdrawal and anxiety symptoms in opioid-dependent patients.
Double-blind, placebo-controlled study evaluating the effects of yohimbine on opioid withdrawal symptoms in methadone-maintained patients compared to healthy volunteers. Yohimbine induced withdrawal symptoms and increased craving in methadone patients, with significant effects on anxiety, blood pressure, and cortisol levels.
Increased plasma norepinephrine response to yohimbine in elderly men.
RCT comparing the effects of yohimbine and clonidine on plasma norepinephrine and epinephrine responses in 5 healthy older men and 18 healthy young men. Plasma norepinephrine increases after yohimbine were greater in older men than in young men, suggesting increased sympathetic nervous system outflow with aging.
Comparison of the effects of clonidine and yohimbine on spontaneous pupillary fluctuations in healthy human volunteers.
RCT comparing the effects of clonidine and yohimbine on spontaneous pupillary fluctuations in 16 healthy male volunteers. Clonidine decreased blood pressure, salivation, and alertness, while yohimbine increased these measures and pupil diameter. The combination of drugs reduced each other's effects.
Comparison of the effects of clonidine and yohimbine on pupillary diameter at different illumination levels.
Double-blind placebo-controlled cross-over study with 16 healthy male volunteers comparing the effects of clonidine and yohimbine on pupil diameter under different illumination levels. Clonidine caused light-dependent miosis, while yohimbine increased pupil size significantly at higher luminance levels.
Cerebrospinal fluid corticotropin-releasing hormone in healthy humans: effects of yohimbine and naloxone.
The study investigated the effects of yohimbine and naloxone on non-HPA CRH neurons in healthy adults. Yohimbine increased CSF norepinephrine and appeared to increase CSF CRH levels, while both yohimbine and naloxone increased plasma cortisol concentrations.
Effects of yohimbine on cerebral blood flow, symptoms, and physiological functions in humans.
RCT using PET to compare cerebral blood flow changes after intravenous yohimbine versus placebo in nine healthy humans. Yohimbine increased symptoms, decreased Paco2 due to hyperventilation, increased blood pressure, and decreased whole-brain CBF, with regional increases in anxiety-related areas.
Biopharmaceutics and metabolism of yohimbine in humans.
The study investigated the biopharmaceutics and pharmacokinetics of yohimbine and its metabolites in healthy subjects following intravenous and oral dosing. The oral absolute bioavailability of yohimbine was found to be 22.3%, with low distribution and renal excretion rates. The elimination rate-limited kinetics for 11-hydroxy-yohimbine was observed.
Effects of Alzheimer's disease and normal aging on cerebrospinal fluid norepinephrine responses to yohimbine and clonidine.
The study compared CSF norepinephrine concentrations following administration of yohimbine, clonidine, and placebo in patients with Alzheimer's disease, older, and young normal subjects. Yohimbine-induced increases in CSF norepinephrine were greater in AD patients and older subjects compared to young subjects. Behavioral arousal was also greater in AD patients.
Effect of yohimbine-trazodone on psychogenic impotence: a randomized, double-blind, placebo-controlled study.
RCT of 63 patients with psychogenic impotence comparing placebo to a combination of yohimbine and trazodone. The combination showed significant improvement in erectile function, with positive results maintained at 3- and 6-month follow-up. Minor adverse effects were reported.
Pharmacokinetic study of yohimbine and its pharmacodynamic effects on salivary secretion in patients treated with tricyclic antidepressants.
Pharmacokinetic study of yohimbine's effects on salivary secretion in patients treated with tricyclic antidepressants. Yohimbine increased salivary outflow and plasma noradrenaline levels, with higher pharmacokinetic parameters in patients than controls. A lower dose increased salivary secretion without side effects, suggesting potential use for dry mouth treatment.
Noradrenergic neuronal dysregulation in panic disorder: the effects of intravenous yohimbine and clonidine in panic disorder patients.
RCT evaluating the effects of intravenous yohimbine and clonidine on noradrenergic neuronal regulation in 15 healthy subjects and 38 panic disorder patients. A subgroup of panic disorder patients experienced yohimbine-induced panic attacks and had larger increases in plasma MHPG compared to healthy subjects.
Effect of yohimbine hydrochloride on erectile impotence: a double-blind study.
A double-blind, partial crossover study on the effect of yohimbine hydrochloride on erectile dysfunction in 82 patients. After 1 month, 14% experienced full restoration of erections, 20% had a partial response, and 65% reported no improvement. Yohimbine showed activity in some patients with arterial insufficiency and other conditions.
Yohimbine increases human salivary secretion.
The study evaluated the effect of oral yohimbine (14 mg) on salivary secretion in healthy volunteers. Yohimbine significantly increased salivary secretion compared to placebo, with effects observed from 60 to 180 minutes after administration.
Is yohimbine effective in the treatment of organic impotence? Results of a controlled trial.
Randomized controlled trial with partial cross-over comparing yohimbine to placebo in 100 organically impotent men. The study found a positive response in 42.6% of patients receiving yohimbine versus 27.6% in the placebo group, but the difference was not statistically significant. Yohimbine showed modest effectiveness at the doses used.
Alpha 2-adrenergic and opiate receptor blockade. Synergistic effects on anxiety in healthy subjects.
RCT evaluating the interaction between opiate and adrenergic systems in healthy humans using naloxone and yohimbine. The combination showed a synergistic effect on anxiety-related symptoms and increased plasma cortisol. Male subjects reported prolonged penile erection with the combination.
Impact of endogenous progesterone on reactivity to yohimbine and cocaine cues in cocaine-dependent women.
RCT examining the impact of endogenous progesterone on subjective and endocrine responses to drug-paired cues in cocaine-dependent women. High progesterone levels attenuated craving and anxiety responses to cues following yohimbine administration, suggesting protective effects against cocaine relapse.
Effects of glucagon-like peptide-1, yohimbine, and nitrergic modulation on sympathetic and parasympathetic activity in humans.
Double-blind study with 48 healthy volunteers assessing the effects of GLP-1 agonist, yohimbine, and l-NMMA on autonomic nervous functions. GLP-1 increased muscle sympathetic nerve activity but did not affect cardiac sympathetic or parasympathetic indices. Yohimbine increased plasma catecholamines and cardiac sympathetic activity.
Yohimbine in neurally mediated syncope. Pathophysiological implications.
RCT evaluating the effect of yohimbine on sympathetic stimulation in patients with neurally mediated syncope (NMS). Yohimbine increased plasma norepinephrine levels and muscle sympathetic nerve activity, preventing syncope in seven out of eight patients, suggesting potential therapeutic use in NMS.
Reversal of sedative and clinicophysiological effects of epidural xylazine and detomidine with atipamezole and yohimbine in buffaloes (Bubalus bubalis).
RCT in buffaloes assessing the reversal of sedative effects of epidural xylazine or detomidine using intravenous yohimbine or atipamezole. Both agents reversed bradycardia, respiratory depression, ruminal stasis, and hypothermia within five to 15 minutes, with atipamezole acting more rapidly than yohimbine.
Noradrenergic and serotonergic function in posttraumatic stress disorder.
RCT involving 26 PTSD patients and 14 healthy subjects receiving yohimbine hydrochloride, m-CPP, or saline. Yohimbine induced panic attacks in 42% of PTSD patients, with increased anxiety and PTSD symptoms. m-CPP induced panic attacks in 31% of PTSD patients, with increased anxiety, PTSD symptoms, and diastolic blood pressure.
Yohimbine elimination in normal volunteers is characterized by both one- and two-compartment behavior.
The study investigated the safety, pharmacodynamic response, and pharmacokinetic profile of yohimbine hydrochloride in 32 healthy volunteers. Yohimbine exhibited one-compartment elimination in most subjects, with dose-dependent increases in Cmax and AUC, but no significant effects on heart rate, blood pressure, or anxiety/mood scores. Plasma catecholamine levels increased significantly with yohimbine AUC and Cmax.
Is high-dose yohimbine hydrochloride effective in the treatment of mixed-type impotence? A prospective, randomized, controlled double-blind crossover study.
RCT of 29 patients with mixed-type impotence comparing high-dose yohimbine hydrochloride to placebo. Positive clinical results were similar between yohimbine and placebo, with no statistical difference. Yohimbine was not more effective than placebo as a treatment.
Behavioral, sympathetic and adrenocortical responses to yohimbine in panic disorder patients and normal controls.
The study examined the effects of oral yohimbine on behavioral, sympathetic, and adrenocortical responses in 7 healthy controls and 11 patients with panic disorder. Yohimbine induced panic episodes in 6 panic disorder patients but not in controls, and significantly raised systolic blood pressure, plasma norepinephrine, and cortisol levels. Panic disorder patients exhibited greater anxiogenic, cardiovascular, and cortisol responses compared to controls.
Yohimbine, erectile capacity, and sexual response in men.
Double-blind, placebo-controlled crossover study assessed the effect of yohimbine on erectile response in men with erectile problems and a sexually functional comparison group. Mixed effects were found, with some men reporting strong positive effects on sexual function, increased frequency of sexual activities, and increased sexual arousal during masturbation but not intercourse.
Serotonergic and noradrenergic dysregulation in alcoholism: m-chlorophenylpiperazine and yohimbine effects in recently detoxified alcoholics and healthy comparison subjects.
RCT comparing serotonergic and noradrenergic reactivity in 22 recently detoxified alcoholic patients and 13 healthy subjects using intravenous infusions of mCPP, yohimbine, or placebo. Both mCPP and yohimbine increased nervousness, vital signs, and plasma cortisol, prolactin, and MHPG levels. Alcoholic patients showed blunted cortisol responses to mCPP and enhanced cortisol responses to yohimbine.
Effect of clonidine and yohimbine on sleep in healthy men: a double-blind, randomized, controlled trial.
Double-blind, randomized, placebo-controlled trial studying the effects of yohimbine and clonidine on sleep in 8 healthy men. Yohimbine showed no apparent effects on sleep, while clonidine reduced REM sleep.
Effects of atipamezole and yohimbine on medetomidine-induced central nervous system depression and cardiorespiratory changes in lambs.
RCT comparing the effects of atipamezole and yohimbine on reversing medetomidine-induced CNS depression and cardiorespiratory changes in lambs. Yohimbine and atipamezole abolished medetomidine-induced tachypnea, but only atipamezole allowed lambs to walk unassisted sooner.
Noradrenergic response to acute ethanol administration in healthy subjects: comparison with intravenous yohimbine.
The study compared the effects of oral ethanol and intravenous yohimbine, alone and in combination, on subjective intoxication, anxiety, plasma MHPG, cortisol, and cardiovascular indices in 12 healthy subjects. Ethanol increased intoxication, anxiety, plasma MHPG, and systolic blood pressure, while yohimbine increased anxiety, plasma MHPG, cortisol, and blood pressure. Combined administration had additive effects on intoxication and plasma MHPG.
Yohimbine-facilitated acoustic startle reflex in humans.
RCT with 7 healthy subjects evaluating the effects of yohimbine on the acoustic startle reflex (ASR). Yohimbine increased startle amplitude and decreased latency, indicating an excitatory effect on ASR and supporting the relationship between increased noradrenergic function and anxiety states.
Anxiogenic properties of yohimbine. II. Influence of experimental set and setting.
Double-blind crossover study administering 20 mg yohimbine or placebo to panic patients and controls to assess stress induction. Yohimbine increased heart rate during a mental arithmetic task in controls but did not potentiate task responses in patients. No panic attacks were observed, suggesting the experimental design may reduce yohimbine's anxiogenic effects.
Does yohimbine act as a slimming drug?
RCT examining yohimbine's effect on weight loss in obese patients on a low-energy diet. Yohimbine significantly increased mean weight loss compared to placebo. No significant effect on lipolysis or gastric emptying was observed.
Yohimbine increases cerebrospinal fluid and plasma norepinephrine but not arginine vasopressin in humans.
RCT measuring the effects of yohimbine on cerebrospinal fluid and plasma norepinephrine and arginine vasopressin in 7 young normal male subjects. Yohimbine increased cerebrospinal fluid and plasma norepinephrine but did not affect arginine vasopressin levels.
The effects of clonidine and yohimbine on human information processing.
RCT testing the effects of clonidine and yohimbine on information processing in six volunteers. Clonidine slowed reaction time (RT) significantly, while yohimbine tended to speed RT, with significant effects only for certain tasks.
Anxiogenic effect of yohimbine in healthy subjects: comparison with caffeine and antagonism by clonidine and diazepam.
Three placebo-controlled double-blind crossover trials analyzed the effects of oral yohimbine (0.8 mg/kg) on mood and performance in 16 healthy students. Yohimbine shifted mood towards panic, elevated systolic blood pressure and plasma prolactin, reduced digit symbol substitution, and induced drowsiness and passiveness. Clonidine and diazepam were tested for antagonistic effects on yohimbine's impact.
Noradrenergic function in schizophrenia.
Double-blind, placebo-controlled study administering yohimbine to 16 healthy subjects and 18 drug-free schizophrenic patients, with and without tardive dyskinesia. The study measured changes in behavior, plasma MHPG level, blood pressure, and heart rate. A subgroup of patients experienced a dysphoric arousal reaction not observed in healthy subjects. The schizophrenic group showed a trend toward increased plasma MHPG level and systolic blood pressure, but no significant differences were found between patients with and without tardive dyskinesia.
Regional fat loss from the thigh in obese women after adrenergic modulation.
RCT involving 28 obese women on a calorie-restricted diet, testing regional fat loss from the thigh using adrenergic modulation. Treatments included isoproterenol injections and creams containing colforsin, aminophylline, and yohimbine. Treated thighs lost significantly more girth compared to placebo.
Behavioral, biochemical, and blood pressure responses to alprazolam in healthy subjects: interactions with yohimbine.
The study investigated the effects of alprazolam and yohimbine, both individually and in combination, on plasma MHPG, cortisol, blood pressure, and subjective behavioral ratings in eight healthy subjects. Alprazolam reduced plasma MHPG, cortisol, and blood pressure, while yohimbine increased plasma MHPG. Yohimbine antagonized the effects of alprazolam on blood pressure and attenuated changes in cortisol and subjective ratings.
Contrasting actions of pressor agents in severe autonomic failure.
RCT in 35 patients with severe orthostatic hypotension due to multiple system atrophy or pure autonomic failure. The study compared the pressor effects of various agents, finding significant increases in systolic blood pressure with phenylpropanolamine, yohimbine, and indomethacin, but not with ibuprofen, caffeine, or methylphenidate.