2778 Venlafaxine Venlafaxine (brand name: Effexor or Efexor) is an effective antidepressant for many persons; Venlafaxine is a bicyclic antidepressant, and is usually categorized as a serotonin-norepinephrine reuptake inhibitor (SNRI), but it has been referred to as a serotonin-norepinephrine-dopamine reuptake inhibitor. It works by blocking the transporter reuptake proteins for key neurotransmitters affecting mood, thereby leaving more active neurotransmitter in the synapse. The neurotransmitters affected are serotonin (5-hydroxytryptamine) and norepinephrine (noradrenaline) Additionally, in high doses it weakly inhibits the reuptake of dopamine; A comparison of adverse event rates in a fixed dose study comparing venlafaxine 75, 225, and 375 mg/day with placebo revealed a dose dependency for some of the more common adverse events associated with venlafaxine use. The rule for including events was to enumerate those that occurred at an incidence of 5% or more for at least one of the venlafaxine groups and for which the incidence was at least twice the placebo incidence for at least one venlafaxine group. Tests for potential dose relationships for these events (Cochran-Armitage Test, with a criterion of exact 2-sided p-value <= 0.05) suggested a dose-dependency for several adverse events in this list, including chills, hypertension, anorexia, nausea, agitation, dizziness, somnolence, tremor, yawning, sweating, and abnormal ejaculation.[Wyeth Monograph]; Venlafaxine is an effective anti-depressant for many persons; however, it seems to be especially effective for those with treatment resistant depression. Some of these persons have taken two or more antidepressants prior to venlafaxine with no relief. Patients suffering with severe long-term depression typically respond better to venlafaxine than other drugs. However, venlafaxine has been reported to be more difficult to discontinue than other antidepressants. In addition, a September 2004 Consumer Reports study ranked venlafaxine as the most effective among six commonly prescribed antidepressants. However, this should not be considered a definitive finding, since responses to psychiatric medications can vary significantly from individual to individual; however, it seems to be especially effective for those with treatment-resistant depression. Some of these persons have taken two or more antidepressants prior to venlafaxine with no relief. Patients suffering with severe long term depression typically respond better to venlafaxine than other drugs. However, venlafaxine has been reported to be more difficult to discontinue than other antidepressants. In addition, a September 2004 Consumer Reports study ranked venlafaxine as the most effective among six commonly prescribed antidepressants. However, this should not be considered a definitive finding, since responses to psychiatric medications can vary significantly from individual to individual; Venlafaxine hydrochloride is a prescription antidepressant that belongs to the class of antidepressants called serotonin-norepinephrine reuptake inhibitors (SNRI). A Black Box Warning has been issued with Venlafaxine and with other SSRI and SNRI anti-depressants advising of risk of suicide. There is an additional risk if a physician misinterprets patient expression of adverse effects such as panic or akithesia. Careful assessment of patient history and comorbid risk factors such as drug abuse are essential in evaluating the safety of Venlafaxine for individual patients. Another risk is Serotonin syndrome. This is a serious effect that can be caused by interactions with other drugs and is potentially fatal. This risk necessitates clear information to patients and proper medical history. Venlafaxine is used primarily for the treatment of depression, generalized anxiety disorder, obsessive compulsive disorder, social anxiety disorder, and panic disorder in adults. It is also used for other general depressive disorders. Although it is not approved for use in children or adolescents, there is a considerable information by Wyeth on cautions if presecribed to this age group. Venlafaxine hydrochloride is a prescription antidepressant first introduced by Wyeth in 1993. It belongs to class of antidepressants called serotonin-norepinephrine reuptake inhibitors (SNRI). As of August 2006, generic venlafaxine is available in the United States. 93413-69-5 5656 C17H27NO2 277.204180 White powder. 215-217°C (Hydrochloride salt) 572 mg/ml (Hydrochloride salt) Oral. Venlafaxine is well absorbed. Food does not effect the absorption of venlafaxine or its subsequent metabolism into ODV. Bioavailability is 45% following oral administration. Time to steady state = 3 days. The exact mechanism of action of venlafaxine is unknown, but appears to be associated with the its potentiation of neurotrasmitter activity in the CNS. Venlafaxine and its active metabolite, O-desmethylvenlafaxine (ODV), inhibit the reuptake of both serotonin and norepinephrine with a potency greater for the 5-HT than for the NE reuptake process. Both venlafaxine and the ODV metabolite have weak inhibitory effects on the reuptake of dopamine but, unlike the tricyclics and similar to SSRIs, they are not active at histaminergic, muscarinic, or alpha(1)-adrenergic receptors. Undergoes extensive first pass metabolism in the liver to its major, active metabolite, ODV, and two minor, less active metabolites, N-desmethylvenlafaxine and N,O-didesmethylvenlafaxine. Formation of ODV is catalyzed by cytochrome P450 (CYP) 2D6, whereas N-demethylation is catalyzed by CYP3A4, 2C19 and 2C9. ODV possesses antidepressant activity that is comparable to that of venlfaxine. Route of Elimination: Renal elimination of venlafaxine and its metabolites is the primary route of excretion. Approximately 87% of a venlafaxine dose is recovered in the urine within 48 hours as either unchanged venlafaxine (5%), unconjugated ODV (29%), conjugated ODV (26%), or other minor inactive metabolites (27%). Half Life: 5 hours Venlafaxine's toxicity appears to be higher than other SSRIs, with a fatal toxic dose closer to that of the tricyclic antidepressants than the SSRIs. Doses of 900 mg or more are likely to cause moderate toxicity. Deaths have been reported following large No indication of carcinogenicity to humans (not listed by IARC). For the management of major depressive disorder (MDD), generalized anxiety disorder (GAD), social anxiety disorder (social phobia), panic disorder with or without agoraphobia, vasomotor symptoms in women with breast cancer and in postmenopausal women, and neuropathic pain. Most patients overdosing with venlafaxine develop only mild symptoms. However, severe toxicity is reported with the most common symptoms being CNS depression, serotonin toxicity, seizure, or cardiac conduction abnormalities. Treatment should consist of those general measures employed in the management of overdosage with any antidepressant. Ensure an adequate airway, oxygenation, and ventilation. Monitor cardiac rhythm and vital signs. General supportive and symptomatic measures are also recommended. Induction of emesis is not recommended. Gastric lavage with a large bore orogastric tube with appropriate airway protection, if needed, may be indicated if performed soon after ingestion or in symptomatic patients. Activated charcoal should be administered. Due to the large volume of distribution of this drug, forced diuresis, dialysis, hemoperfusion, and exchange transfusion are unlikely to be of benefit. No specific antidotes for venlafaxine are known. (L1712) 2009-07-21T20:26:28Z 2014-12-24T20:25:50Z Venlafaxine C07187 9943 Venlafaxine DB00285 true COC1=CC=C(C=C1)C(CN(C)C)C1(O)CCCCC1 C17H27NO2 InChI=1/C17H27NO2/c1-18(2)13-16(17(19)11-5-4-6-12-17)14-7-9-15(20-3)10-8-14/h7-10,16,19H,4-6,11-13H2,1-3H3 InChIKey=PNVNVHUZROJLTJ-UHFFFAOYNA-N 277.4018 277.204179113 Exogenous Solid HMDB05016 CHEMBL637 5454 <p>Thomas P. Jerussi, Chrisantha H. Senanayake, &#8220;Derivatives of (+)-venlafaxine and methods of preparing and using the same.&#8221; U.S. Patent US6197828, issued June, 1994.</p>