What is the recommended dosage of venlafaxine (Effexor)?

Venlafaxine (Effexor) Dosage Recommendations

The recommended starting dose for venlafaxine is 75 mg/day, administered in two or three divided doses, taken with food, with dose increases up to 225 mg/day for outpatients and potentially up to 375 mg/day for more severely depressed inpatients. 1

Initial Dosing and Titration

• Starting dose is 75 mg/day, divided into two or three doses, and should be taken with food 1
• Dose increases should be made in increments of up to 75 mg/day at intervals of no less than 4 days 1
• For outpatients with moderate depression, doses up to 225 mg/day are recommended 1
• For severely depressed inpatients, doses up to 350-375 mg/day may be beneficial 1, 2

Dosage Based on Clinical Setting and Severity

• Treatment setting is the most important factor in determining dosage, with inpatients typically receiving higher doses than outpatients 3
• Severity of illness and history of previous treatment with antidepressants are associated with higher dosage requirements 3
• For most outpatients, 75-225 mg/day is sufficient 1, 3
• Very high doses (≥375 mg/day) may provide additional benefits in extremely ill patients 3, 4

Dosage Adjustments for Special Populations

• Hepatic impairment: Reduce total daily dose by 50% in patients with mild to moderate hepatic impairment; further individualization may be necessary for patients with cirrhosis 1
• Renal impairment: Reduce total daily dose by 25% for mild to moderate renal impairment (GFR 10-70 mL/min) and by 50% for patients undergoing hemodialysis 1
• Elderly patients: No specific dose adjustment is recommended based on age alone, but caution should be exercised when increasing the dose 1

Dosage for Specific Indications

• For neuropathic pain: The efficacious dosage range is typically 150-225 mg/day, with a minimum effective dose of 75 mg/day 5
• For depression: Standard dosing applies, with 75-225 mg/day for outpatients and up to 375 mg/day for severe inpatient depression 1, 2

Monitoring and Safety Considerations

• Blood pressure monitoring is important, as venlafaxine can cause dose-dependent increases in blood pressure, particularly at higher doses 5, 2
• At doses ≤200 mg/day, 3-5% of patients experience blood pressure elevation; at 201-300 mg/day, 7%; and at >300 mg/day, 13% (compared to 2% with placebo) 2
• Cardiac conduction abnormalities have been reported in a small number of patients, requiring caution in those with cardiac disease 5
• Common adverse effects include nausea (most common but typically resolves within 1-3 weeks), somnolence, insomnia, dizziness, constipation, sweating, and nervousness 2
• Side effects are generally dose-related, with higher doses associated with increased severity but not necessarily higher discontinuation rates 4

Maintenance Treatment

• For major depressive disorder, sustained pharmacological therapy beyond the acute response phase is generally recommended 1
• Long-term efficacy has been demonstrated in maintenance treatment studies 1
• When discontinuing venlafaxine, tapering over 10-14 days is recommended to limit withdrawal symptoms 5

Practical Considerations

• A stepwise dosage regimen is suggested, with dose increases in cases of non-response before discontinuing treatment 3
• For most patients, 75 mg/day is an appropriate starting dose, with increases based on clinical response and tolerability 1, 3
• Higher doses (>300 mg/day) have been shown to be tolerable but are associated with increased frequency and severity of side effects 4