EFFEXOR XR® (venlafaxine Extended-Release) Capsules

EFFEXOR XR® (venlafaxine Extended-Release) Capsules

EFFEXOR XR® (venlafaxine Extended-Release) Capsules

Effexor XR is an extended-release capsule for once-a-day oral administration that contains venlafaxine hydrochloride, a SNRI.

Venlafaxine is designated (R/S)-1-[2-(dimethylamino)-1-(4-methoxyphenyl)ethyl] cyclohexanol hydrochloride or (±)-1-[α- [(dimethylamino)methyl]-p-methoxybenzyl] cyclohexanol hydrochloride and has the empirical formula of C17H27NO2 HCl. Its molecular weight is 313.86.

Drug release is controlled by diffusion through the coating membrane on the spheroids and is not pH-dependent. Capsules contain venlafaxine hydrochloride equivalent to 37.5 mg, 75 mg, or 150 mg venlafaxine. Inactive ingredients consist of cellulose, ethylcellulose, gelatin, hypromellose, iron oxide, and titanium dioxide.

INDICATIONS AND USAGE

Major Depressive Disorder

Effexor XR (venlafaxine hydrochloride) extended-release capsules are indicated for the treatment of major depressive disorder (MDD). Efficacy was established in three short-term (4, 8, and 12 weeks) and two long-term, maintenance trials.

Generalized Anxiety Disorder

Effexor XR is indicated for the treatment of Generalized Anxiety Disorder (GAD). Efficacy was established in two 8-week and two 26-week placebo-controlled trials.

Social Anxiety Disorder

Effexor XR is indicated for the treatment of Social Anxiety Disorder (SAD), also known as social phobia. Efficacy was established in four 12-week and one 26-week, placebo-controlled trials.

Panic Disorder

Effexor XR is indicated for the treatment of Panic Disorder (PD), with or without agoraphobia. Efficacy was established in two 12-week placebo-controlled trials.

Mechanism of Action

The exact mechanism of the antidepressant action of venlafaxine in humans is unknown, but is thought to be related to the potentiation of serotonin and norepinephrine in the central nervous system, through inhibition of their reuptake. Non- clinical studies have demonstrated that venlafaxine and its active metabolite, ODV, are potent and selective inhibitors of neuronal serotonin and norepinephrine reuptake and weak inhibitors of dopamine reuptake.

DOSAGE AND ADMINISTRATION

Effexor XR should be administered in a single dose with food, either in the morning or in the evening at approximately the same time each day. Each capsule should be swallowed whole with fluid and not divided, crushed, chewed, or placed in water or it may be administered by carefully opening the capsule and sprinkling the entire contents on a spoonful of applesauce. This drug/food mixture should be swallowed immediately without chewing and followed with a glass of water to ensure complete swallowing of the pellets (spheroids).

Major Depressive Disorder

For most patients, the recommended starting dose for Effexor XR is 75 mg per day, administered in a single dose. For some patients, it may be desirable to start at 37.5 mg per day for 4 to 7 days to allow new patients to adjust to the medication before increasing to 75 mg per day. Patients not responding to the initial 75 mg per day dose may benefit from dose increases to a maximum of 225 mg per day. Dose increases should be in increments of up to 75 mg per day, as needed, and should be made at intervals of not less than 4 days, since steady-state plasma levels of venlafaxine and its major metabolites are achieved in most patients by day 4.

Generalized Anxiety Disorder

For most patients, the recommended starting dose for Effexor XR is 75 mg per day, administered in a single dose. For some patients, it may be desirable to start at 37.5 mg per day for 4 to 7 days to allow new patients to adjust to the medication before increasing to 75 mg per day. Patients not responding to the initial 75 mg per day dose may benefit from dose increases to a maximum of 225 mg per day. Dose increases should be in increments of up to 75 mg per day, as needed, and should be made at intervals of not less than 4 days, since steady-state plasma levels of venlafaxine and its major metabolites are achieved in most patients by day 4.

Social Anxiety Disorder (Social Phobia)

The recommended dose is 75 mg per day, administered in a single dose. There was no evidence that higher doses confer any additional benefit.

Panic Disorder

The recommended starting dose is 37.5 mg per day of Effexor XR for 7 days. Patients not responding to 75 mg per day may benefit from dose increases to a maximum of approximately 225 mg per day. Dose increases should be in increments of up to 75 mg per day, as needed, and should be made at intervals of not less than 7 days.

Switching Patients from Effexor Tablets

Depressed patients who are currently being treated at a therapeutic dose with Effexor (immediate release) may be switched to Effexor XR at the nearest equivalent dose (mg per day), e.g., 37.5 mg venlafaxine twice a day to 75 mg Effexor XR once daily. However, individual dosage adjustments may be necessary.

Discontinuing Effexor XR

A gradual reduction in the dose, rather than abrupt cessation, is recommended when discontinuing therapy with Effexor XR. In clinical studies with Effexor XR, tapering was achieved by reducing the daily dose by 75 mg at one-week intervals. Individualization of tapering may be necessary. In some patients, discontinuation may need to occur over a period of several months.

Switching Patients to or from a Monoamine Oxidase Inhibitor (MAOI) Intended to Treat Psychiatric Disorders

At least 14 days should elapse between discontinuation of an MAOI (intended to treat psychiatric disorders) and initiation of therapy with Effexor XR. In addition, at least 7 days should be allowed after stopping Effexor XR before starting an MAOI intended to treat psychiatric disorders.

CONTRAINDICATIONS

Hypersensitivity

Hypersensitivity to venlafaxine hydrochloride, desvenlafaxine succinate or to any excipients in the formulation.

Concomitant Use with Monoamine Oxidase Inhibitors (MAOIs)

The use of MAOIs (intended to treat psychiatric disorders) concomitantly with Effexor XR or within 7 days of discontinuing treatment with Effexor XR is contraindicated because of an increased risk of serotonin syndrome. The use of Effexor XR within 14 days of discontinuing treatment with an MAOI (intended to treat psychiatric disorders) is also contraindicated.

WARNINGS AND PRECAUTIONS

  • Increased risk of suicidal thinking and behavior in children, adolescents and young adults taking antidepressants.
  • Monitor for worsening and emergence of suicidal thoughts and behaviors
  • Effexor XR is not approved for use in pediatric patients
  • Clinical Worsening/Suicide Risk: Monitor for clinical worsening and suicide risk.
  • Serotonin Syndrome: Risk increases with concomitant use of other serotonergic drugs. Discontinue Effexor XR and initiate supportive treatment if serotonin syndrome occurs.
  • Elevations in Blood Pressure: Control hypertension before initiating treatment. Monitor blood pressure regularly during treatment.
  • Abnormal Bleeding: Effexor XR may increase risk of bleeding events. Caution patients about the risk of bleeding associated with the concomitant use of Effexor XR and NSAIDs, aspirin, or other drugs that affect coagulation.
  • Angle Closure Glaucoma: Angle closure glaucoma has occurred in patients with untreated anatomically narrow angles treated with antidepressants.
  • Activation of Mania/Hypomania: Use cautiously in patients with bipolar disorder. Caution patients about the risk of activation of mania/hypomania.
  • Sexual Dysfunction: Effexor XR may cause symptoms of sexual dysfunction

Adverse Reactions

Body as a whole – Anaphylaxis, angioedema

Cardiovascular system – QT prolongation, ventricular fibrillation, ventricular tachycardia (including torsade de pointes), takotsubo cardiomyopathy

Digestive system – Pancreatitis

Hemic/Lymphatic system – Mucous membrane bleeding, blood dyscrasias (including agranulocytosis, aplastic anemia, neutropenia and pancytopenia), prolonged bleeding time, thrombocytopenia

Metabolic/Nutritional – Hyponatremia, Syndrome of Inappropriate Antidiuretic Hormone (SIADH) secretion, abnormal liver function tests, hepatitis, prolactin increased

Musculoskeletal – Rhabdomyolysis

Nervous system – Neuroleptic Malignant Syndrome (NMS), serotonergic syndrome, delirium, extrapyramidal reactions (including dystonia and dyskinesia), impaired coordination and balance, tardive dyskinesia

Respiratory system – Dyspnea, interstitial lung disease, pulmonary eosinophilia

Skin and appendages – Stevens-Johnson syndrome, toxic epidermal necrolysis, erythema multiforme

Special senses – Angle-closure glaucoma

DRUG INTERACTIONS

Central Nervous System (CNS)-Active Drugs: The risk of using venlafaxine in combination with other CNS-active drugs has not been systematically evaluated. Consequently, caution is advised when Effexor XR is taken in combination with other CNS-active drugs.

Monoamine Oxidase Inhibitors: Adverse reactions, some of which were serious, have been reported in patients who have recently been discontinued from an MAOI and started on antidepressants with pharmacological properties similar to Effexor XR (SNRIs or SSRIs), or who have recently had SNRI or SSRI therapy discontinued prior to initiation of an MAOI.

Serotonergic Drugs: Based on the mechanism of action of Effexor XR and the potential for serotonin syndrome, caution is advised when Effexor XR is coadministered with other drugs that may affect the serotonergic neurotransmitter systems, such as triptans, SSRIs, other SNRIs, linezolid (an antibiotic which is a reversible non-selective MAOI), lithium, tramadol, or St. John’s wort. If concomitant treatment with Effexor XR and these drugs is clinically warranted, careful observation of the patient is advised, particularly during treatment initiation and dose increases. The concomitant use of Effexor XR with tryptophan supplements is not recommended.

Drugs that Interfere with Hemostasis (e.g., NSAIDs, Aspirin, and Warfarin): Serotonin release by platelets plays an important role in hemostasis. The use of psychotropic drugs that interfere with serotonin reuptake is associated with the occurrence of upper gastrointestinal bleeding and concurrent use of an NSAID or aspirin may potentiate this risk of bleeding. Altered anticoagulant effects, including increased bleeding, have been reported when SSRIs and SNRIs are coadministered with warfarin. Patients receiving warfarin therapy should be carefully monitored when Effexor XR is initiated or discontinued.

Weight Loss Agents: The safety and efficacy of venlafaxine therapy in combination with weight loss agents, including phentermine, have not been established. Coadministration of Effexor XR and weight loss agents is not recommended. Effexor XR is not indicated for weight loss alone or in combination with other products.

Drug-Laboratory Test Interactions

False-positive urine immunoassay screening tests for phencyclidine (PCP) and amphetamine have been reported in patients taking venlafaxine. This is due to lack of specificity of the screening tests. False positive test results may be expected for several days following discontinuation of venlafaxine therapy. Confirmatory tests, such as gas chromatography/mass spectrometry, will distinguish venlafaxine from PCP and amphetamine.

USE IN SPECIFIC POPULATIONS

Pregnancy

Teratogenic Effects – Pregnancy Category C: There are no adequate and well-controlled studies in pregnant women. Effexor XR should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Labor and Delivery

The effect of venlafaxine on labor and delivery in humans is unknown.

Nursing Mothers

Venlafaxine and ODV have been reported to be excreted in human milk. Because of the potential for serious adverse reactions in nursing infants from Effexor XR, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Pediatric Use

Anyone considering the use of Effexor XR in a child or adolescent must balance the potential risks with the clinical need.

OVERDOSAGE

During the premarketing evaluations of Effexor XR (for MDD, GAD, SAD, and PD) and Effexor (for MDD), there were twenty reports of acute overdosage with Effexor (6 and 14 reports in Effexor XR and Effexor patients, respectively), either alone or in combination with other drugs and/or alcohol.

Somnolence was the most commonly reported symptom. Among the other reported symptoms were paresthesia of all four limbs, moderate dizziness, nausea, numb hands and feet, and hot-cold spells 5 days after the overdose. In most cases, no signs or symptoms were associated with overdose. The majority of the reports involved ingestion in which the total dose of venlafaxine taken was estimated to be no more than several-fold higher than the usual therapeutic dose. One patient who ingested 2.75 g of venlafaxine was observed to have two generalized convulsions and a prolongation of QTc to 500 msec, compared with 405 msec at baseline. Mild sinus tachycardia was reported in two of the other patients.

Actions taken to treat the overdose included no treatment, hospitalization and symptomatic treatment, and hospitalization plus treatment with activated charcoal. All patients recovered.

In postmarketing experience, overdose with venlafaxine has occurred predominantly in combination with alcohol and/or other drugs. The most commonly reported events in overdosage include tachycardia, changes in level of consciousness (ranging from somnolence to coma), mydriasis, seizures, and vomiting.

Electrocardiogram changes (e.g., prolongation of QT interval, bundle branch block, QRS prolongation), ventricular tachycardia, bradycardia, hypotension, rhabdomyolysis, vertigo, liver necrosis, serotonin syndrome, and death have been reported.

Management of Overdosage

In case of an overdose, provide supportive care, including close medical supervision and monitoring. Treatment should consist of those general measures employed in the management of overdosage with any drug. Consider the possibility of multiple drug overdose. Ensure an adequate airway, oxygenation, and ventilation. Monitor cardiac rhythm and vital signs. Provide supportive and symptomatic measures.

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