Summary
Synopsis
Venlafaxine is a phenylethylamine derivative which facilitates neurotransmission in the brain by blocking presynaptic reuptake of serotonin (5-hydroxytryptamine; 5-HT) and noradrenaline (norepinephrine). Clinical data from patients with major depression are consistent with the favourable efficacy and tolerability profile of venlafaxine predicted by pharmacodynamic studies.
In patients with major depression, venlafaxine 75 to 375 mg/day administered for 6 weeks was significantly more effective than placebo, and at least as effective as imipramine, clomipramine, trazodone or fluoxetine. Venlafaxine is well tolerated, being associated with fewer anticholinergic and CNS adverse effects than tricyclic antidepressants. Unlike the tricyclic antidepressants, venlafaxine does not appear to significantly affect cardiac conduction, although there have been a few reports of modest increases in blood pressure, particularly after high doses of the drug.
In conclusion, wider clinical experience is required to better characterise and confirm potential advantages of venlafaxine compared with other antidepressant agents. These advantages may include a rapid onset of action and reduced propensity to cause anticholinergic effects and cardiotoxicity compared with tricyclic antidepressants. Nevertheless, at this stage venlafaxine offers a more attractive treatment option than tricyclic antidepressants for patients with major depression, primarily because of its good overall tolerability profile.
Pharmacological Properties
Venlafaxine is a phenylethylamine derivative possessing a neuropharmacological profile which differs from that of tricyclic antidepressant drugs. In vitro, venlafaxine inhibits synaptosomal reuptake of both serotonin (5-hydroxytryptamine; 5-HT) and noradrenaline (norepinephrine); the drug is a relatively weak inhibitor of dopamine reuptake. Its potency in inhibiting serotonin reuptake is approximately 5 times that of its noradrenaline reuptake inhibitory activity. The antidepressant potential of venlafaxine has also been demonstrated in in vivo models of depression. Venlafaxine has no significant affinity for adrenergic, muscarinic cholinergic or histamine H1 receptors. Venlafaxine exists as a racemic mixture of (−) and (+) enantiomers. The (−) enantiomer inhibits noradrenaline and serotonin presynaptic reuptake, while the (+) enantiomer primarily inhibits serotonin reuptake. Single and multiple doses of venlafaxine have been shown to produce modest increases in blood pressure in healthy volunteers and patients with depression.
Venlafaxine undergoes extensive first-pass metabolism to the major O-demethyl metabolite, and 2 minor metabolites. O-demethylvenlafaxine inhibits noradrenaline and serotonin reuptake with similar potencies to those of the parent compound. Excretion of venlafaxine and its metabolites is primarily by the renal route, with only 4.7% of an administered dose appearing in urine as unchanged drug. The elimination half-life of venlafaxine is approximately 4 hours and that of O-demethylvenlafaxine is about 10 hours. There were no apparent differences in steady-state pharmacokinetics when 2 and 3 times daily regimens were compared. Clearance of venlafaxine and O-demethylvenlafaxine was reduced by 55% in patients with severe renal impairment and by 33% in patients with cirrhosis.
Therapeutic Efficacy
Available clinical data have demonstrated the antidepressant efficacy of venlafaxine during 6 weeks’ treatment of patients with major depression. Dosages of 75 to 375 mg/day administered as 2 or 3 times daily regimens produced significantly greater improvements in total scores of several depression rating scales versus placebo. In comparisons with other antidepressants generally administered at standard dosages, the efficacy of venlafaxine 75 to 225 mg/day was at least comparable to that of clomipramine, imipramine, trazodone and fluoxetine. Initial data suggest that the onset of action of venlafaxine is about 2 weeks and that its antidepressant activity is maintained for up to 1 year.
Tolerability
Venlafaxine administered at dosages of up to 450 mg/day was well tolerated during short term therapy. Most adverse events were of mild to moderate severity, with many resolving during continued treatment. Venlafaxine 75 to 225 mg/day was better tolerated than clomipramine and imipramine, and as well tolerated as trazodone and fluoxetine. Long term venlafaxine treatment appears to be well tolerated. Generally, venlafaxine does not appear to adversely affect the cardiovascular system; the clinical significance of modest increases in blood pressure reported in a few studies has not been established. The drug does not appear to affect psychomotor performance.
Dosage and Administration
The recommended starting dosage of venlafaxine is 75mg daily administered as a 2 or 3 times daily regimen and this may be increased to a maximum of 375 mg/day administered in 3 divided doses. Regular blood pressure monitoring is recommended. The dosage of venlafaxine should be reduced in patients with hepatic or renal impairment. Concomitant administration of venlafaxine and a monoamine oxidase inhibitor is contraindicated.
Similar content being viewed by others
References
Meltzer HY, Coyle JT, Bunney Jr WE, et al, editors. Psychopharmacology. The third generation of progress. New York: Raven Press, 1987.
Muth EA, Haskins JT, Moyer JA, et al. Antidepressant biochemical profile of the novel bicyclic compound Wy-45,030, an ethyl cyclohexanol derivative. Biochem Pharmacol 1986; 35: 4493–7.
Muth EA, Moyer JA, Haskins JT, et al. Biochemical, neurophysiological, and behavioral effects of Wy-45,233 and other identified metabolites of the antidepressant venlafaxine. Drug Dev Res 1991; 23: 191–9.
Bolden-Watson C, Richelson E. Blockade by newly-developed antidepressants of biogenic amine uptake into rat brain synaptosomes. Life Sci 1993; 52: 1023–9.
Moyer JA, Muth EA, Haskins JT, et al. In vivo antidepressant profiles of the novel bicyclic compounds Wy-45,030 and Wy-45,881 [abstract no. 76.12]. Soc Neurosci 1984; 10: 261.
Haskins JT, Moyer JA, Muth EA, et al. DMI, WY-45,030, WY-45,881 and ciramadol inhibit locus coeruleus neuronal activity. Eur J Pharmacol 1985; 115: 139–46.
Muth EA, Moyer JA, Andree TH. A pharmacological profile of WY-45,233, the major metabolite in humans of the novel bicyclic antidepressant candidate, WY-45,030 [abstract no. 130.4]. Soc Neurosci Abstracts 1986; 12: 473.
Lloyd K, Mitchell P. Preclinical evaluation of venlafaxine, a novel antidepressant drug, in behavioural models of antidepressant activity [abstract]. 21st Annual Meeting of the American College of Neuropsychopharmacology, San Juan, Dec, 1992; 190.
Mitchell PJ, Fletcher A. Venlafaxine exhibits pre-clinical antidepressant activity in the resident-intruder social interaction paradigm. Neuropharmacology 1993; 32: 1001–9.
Nader MA, Wool verton WL. Evaluation of the discriminative stimulus effects of venlafaxine, a potential antidepressant, in rhesus monkeys. Drug Dev Res 1992; 25: 75–80.
Saletu B, Grünberger J, Anderer P, et al. Pharmacodynamics of venlafaxine evaluated by EEG brain mapping, psychometry and psychophysiology. Br J Clin Pharm 1992; 33: 589–601.
Semlitsch HV, Anderer P, Saletu B, et al. Acute effects of the novel antidepressant venlafaxine on cognitive event-related potentials (P300), eye blink rate and mood in young healthy subjects. Int Clin Psychopharmacol 1993; 8: 155–66.
Troy S, Piergies A, Lucki I, et al. Venlafaxine pharmacokinetics and pharmacodynamics [abstract]. Clin Neuropharmacol 1992; 15 Suppl. 1: 324B.
Fabre LF, PutmanIII HP. An ascending single-dose tolerance study of WY-45,030, a bicyclic antidepressant, in healthy men. Curr Ther Res 1987; 42: 901–9.
Schweizer E, Weise C, Clary C, et al. Placebo-controlled trial of venlafaxine for the treatment of major depression. J Clin Psychopharmacol 1991; 11: 233–6.
Cunningham LA, Borison RL, Carman JS, et al. A comparison of venlafaxine, trazodone, and placebo in major depression. J Clin Psychopharmacol 1994; 14: 99–106.
Ferguson J, Khan A, Kucharik R, et al. A placebo-controlled comparative study of the effects on blood pressure and antidepressant efficacy of venlafaxine and imipramine. Neuropsychopharmacology 1994; 10(2): P–117–45.
Gründer G, Wetzel H, Schlöβer R, et al. Subchronic antidepressant treatment with venlafaxine or imipramine and effects on blood pressure: assessment by automatical 24 hour monitoring [abstract]. Pharmacopsychiatry 1993; 26: 155.
Klamerus KJ, Maloney K, Rudolph RL, et al. Introduction of a composite parameter to the pharmacokinetics of venlafaxine and its active O-desmethyl metabolite. J Clin Pharmacol 1992; 32: 716–24.
Sisenwine SF, Politowski J, Birk K, et al. A prefatory investigation of the metabolic disposition of Wy-45,030 in man [abstract no. 1600]. Acta Pharmacol Toxicol 1986; 59 Suppl. 5: 312.
Wang CP, Howell SR, Scatina J, et al. The disposition of venlafaxine enantiomers in dogs, rats, and humans receiving venlafaxine. Chirality 1992; 4: 84–90.
Sellers EM, Ball SE, Cheung SW, et al. Inhibition by venlafaxine (VF) and other 5 HT uptake inhibitors of the polymorphic enzyme CYP2D6 [abstract]. 22nd Annual Meeting of the American College of Neuropsychopharmacology, Honolulu, Dec 13–17, 1993; 163.
Howell SR, Husbands GEM, Scatina JA, et al. Metabolic disposition of 14C-venlafaxine in mouse, rat, dog, rhesus monkey and man. Xenobiotica 1993; 23: 349–59.
Parker V, Pruitt L, Maloney K, et al. Effect of age and sex on the pharmacokinetics of venlafaxine. J Clin Pharmacol 1990; 30: 832.
Troy S, Parker V, Fruncillo R, et al. The pharmacokinetics of venlafaxine when administered in a twice daily regimen. Wyeth-Ayerst (Philadelphia) data on file.
Mendels J, Johnston R, Mattes J, et al. Efficacy and safety of b.i.d. doses of venlafaxine in a dose-response study. Psychopharmacol Bull 1993; 29: 169–74.
Shrivastava R, Patrick R, Scherer N, et al. A dose-response study of venlafaxine [abstract no. P-174-36]. Neuropsychopharmacology 1994; 10(2): 221S.
Troy S, Schultz RW, Parker VD, et al. The effect of renal disease on the disposition of venlafaxine. Clin Pharmacol Ther 1994; 56: 14–21.
Troy S, Bulow L, Wallace DW. Pharmacokinetic and statistical evaluation of the effect of hepatic disease on the disposition of venlafaxine: final report. Wyeth-Ayerst (Philadelphia) data on file.
Brøsen K. Recent developments in hepatic drug oxidation. Implications for clinical pharmacokinetics. Clin Pharmacokinet 1990; 18: 220–39.
Otton SV, Wu D, Joffe RT, et al. Inhibition by fluoxetine of cytochrome P450 2D6 activity. Clin Pharmacol Ther 1993; 53: 401–9.
Parker V, Troy S, Rudolph R, et al. The potential pharmacokinetic interaction between venlafaxine and lithium carbonate [abstract no. 110]. J Clin Pharmacol 1991; 31: 867.
Troy S, Albert GR, Wallace DW. Pharmacokinetic and statistical evaluation of the potential drug-drug interaction of 50 mg venlafaxine q8h and a single 600 mg lithium dose: final report. Wyeth-Ayerst (Philadelphia) data on file.
Troy S, Turner M, Unruh M, et al. Pharmacokinetic and pharmacodynamic evaluation of the potential drug interaction between venlafaxine and ethanol. Wyeth-Ayerst (Philadelphia) data on file.
Marley E, Wozniak KM. Clinical and experimental aspect of interactions between amine oxidase inhibitors and amine reuptake inhibitors. Psychol Med 1983; 13: 735–49.
Mendels J. Clinical experience with serotonin reuptake inhibiting antidepressants. J Clin Psych 1987; 48 Suppl. 3: 26–30.
Reimherr FW, Byerley WF, Ward MF, et al. Sertraline, a selective inhibitor of serotonin uptake, for the treatment of outpatients with major depressive disorder. Psychopharmacol Bull 1988; 24: 200–5.
Nolan L, o’Malley K. Adverse effects of antidepressants in the elderly. Drugs Aging 1992; 2: 450–8.
Gerstenblith G, Lakatta EG. Disorders of the heart. In: Hazard et al., editors. Principles of geriatric medicine and gerontology, 2nd ed. New York: McGraw-Hill, 1990: 466–75.
Goldberg HL, Finnerty R. An open-label, variable-dose study of WY-45,030 (venlafaxine) in depressed outpatients. Psychopharmacol Bull 1988; 24: 198–9.
Schweizer E, Clary C, Weise C, et al. An open-label, dose-finding study of WY-45,030, a novel bicyclic antidepressant. Psychopharmacol Bull 1988; 24: 195–7.
Guelfi JD, White C, Magni G. A randomized, double-blind comparison of venlafaxine and placebo in inpatients with major depression and melancholia [abstract]. Clin Neuropharmacol 1992; 15 Suppl. 1: 323B.
Guelfi J, White C, Hackett D, et al. Effectiveness of venlafaxine in patients hospitalized for major depression and melancholia. Wyeth-Ayerst Research (Philadelphia) data on file.
Khan A, Fabre LF, Rudolph R. Venlafaxine in depressed outpatients. Psychopharmacol Bull 1991; 27: 141–4.
Magni G, Hackett D. An open-label evaluation of the long-term safety and clinical acceptability of venlafaxine in depressed patients [abstract]. Clin Neuropharmacol 1992; 15 Suppl. 1: 323B.
Tiller J, Johnson G, O’sullivan B, et al. Venlafaxine: a long term study [abstract]. Clin Neuropharmacol 1992; 14 Suppl. 1: 342B.
White C, Hackett D. An open-label evaluation of the long-term safety of oral venlafaxine tablets in depressed geriatric patients: final report. Wyeth Ay erst (Philadelphia) data on file.
Entsuah R, Rudolph R, Derivan A, et al. A low relapse rate confirms the long term efficacy of venlafaxine in the treatment of major depression [abstract]. 22nd Annual Meeting of the American College of Neuropsychopharmacology, Honolulu, Dec 13–17, 1993; 192.
Nierenberg AA, Feighner JP, Rudolph R, et al. Venlafaxine for treatment-resistant unipolar depression. J Clin Psychopharmacol. In press.
Samuelian JC, Tatossian A, Hackett D. A randomized, doubleblind, parallel group comparison of venlafaxine and clomipramine in outpatients with major depression [abstract]. Clin Neuropharmacol 1992; 15 Suppl. 1: 324B.
Clerc GE, Ruimy P, Verdeau-Paillès J. A double-blind comparison of venlafaxine and fluoxetine in patients hospitalized for major depression and melancholia. Int Clin Psychopharmacol 1994; 9: 139–43.
Shrivastava RK, Cohn C, Crowder J, et al. Long-term safety and clinical acceptability of venlafaxine and imipramine in outpatients with major depression. J Clin Psychopharmacol 1994; 14: 322–9.
Schweizer E, Feighner J, Mandos LA, et al. Comparison of venlafaxine and imipramine in the acute treatment of major depression in outpatients. J Clin Psych 1994; 55: 104–8.
Miska SP, Pallay AG, Leventer S. A double-blind, randomized, placebo-controlled evaluation of three twice-daily doses of venlafaxine in patients with major depression: final report. Wyeth-Ayerst (Philadelphia) data on file.
Rudolph R, Entsuah R, Derivan A. Early clinical response in depression to venlafaxine hydrochloride [abstract no. P-26–12]. Biol Psych 1991; 29: 630S.
Åsberg M, Schalling D, Träskman-Bendz L, et al. Psychobiology of suicide, impulsivity, and related phenomena. In: Meltzer et al., editors. Psychopharmacology. The third generation of progress. New York: Raven Press, 1987: 655–68.
Wyeth-Ayerst. Venlafaxine prescribing information, Philadelphia, Pennsylvania, USA, 1994.
Katon W. The epidemiology of depression in medical care. Int J Psych Med 1987; 17: 93–112.
National Institutes Health Consensus Development Panel on Depression in Late Life. Diagnosis and treatment of depression in late life. JAMA 1992; 268: 1018–24.
Burke KC, Burke JD, Rae DS, et al. Comparing age at onset of major depression and other psychiatric disorders by birth cohorts in five US community populations. Arch Gen Psych 1991; 48: 789–95.
Cross-National Collaborative Group. The changing rate of major depression. Cross-national comparisons. JAMA 1992; 268: 3098–105.
Author information
Authors and Affiliations
Additional information
Various sections of the manuscript reviewed by: P. Beck, Frederiksborg General Hospital, Psychiatric Institute, Hillerød, Denmark; G. Chouinard, Clinical Psychopharmacology Unit, Allan Memorial Institute, Montreal, Quebec, Canada; C.K. Cohn, Department of Psychiatry, University of Texas, Houston, Texas, USA; J.M. Davis, Illinois State Psychiatric Institute, Chicago, Illinois, USA; M.H. Lader, Institute of Psychiatry, University of London, London, England; B.E. Leonard, Pharmacology Department, University College, Galway, Ireland; S.A. Montgomery, Department of Psychiatry, St Mary’s Hospital Medical School, London, England; C.Q. Mountjoy, St Andrew’s Hospital, Northampton, England; M.A. Nader, Comparative Medicine Clinical Research Center, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, North Carolina, USA; M.E. Newman, Biological Psychiatry Laboratory, Hadassah-Hebrew University Medical Center, Jerusalem, Israel; T.R. Norman, Department of Psychiatry, University of Melbourne, Heidelberg, Victoria, Australia; K. Pacey, University of Houston, Houston, Texas, USA; K. Rickels, Department of Psychiatry, University of Pennsylvania, Philadelphia, Pennsylvania, USA; B. Saletu, Department of Pharmacopsychiatry and Sleep Research, School of Medicine, University of Vienna, Vienna, Austria; R. Schreiber, Centre de Recherche de Croissy, Croissy-sur-Seine, France; E. Schweizer, Department of Psychiatry, University of Pennsylvania, Philadelphia, Pennsylvania, USA; E.K.G. Syvälahti, Department of Pharmacology, University of Turku, Turku, Finland; M.R. Trimble, Institute of Neurology, University of London, London, England.
Rights and permissions
About this article
Cite this article
Holliday, S.M., Benfield, P. Venlafaxine. Drugs 49, 280–294 (1995). https://doi.org/10.2165/00003495-199549020-00010
Published:
Issue Date:
DOI: https://doi.org/10.2165/00003495-199549020-00010