Dose-Related Paresthesias With Venlafaxine

Abstract

Introduction:

Venlafaxine is a serotonin norepinephrine reuptake inhibitor that is used for mood, anxiety, and pain disorders. We report a case of dose-related paresthesias in association with venlafaxine use in a patient with major depressive disorder. Case report: A young male patient with major depression started treatment with venlafaxine XR at 37.5 mg/d, and the dose was titrated to 75 mg/d with no significant adverse effects. Upon increasing the dose to 150 mg/d, the patient reported tingling, numbness, and itching in his upper extremities. The dose was reduced to 75 mg/d, at which time, the symptoms disappeared. Since the patient still had target symptoms of depression, the patient was willing to try increasing the dose back to 150 mg/d. Upon rechallenge, the tingling, numbness, and itching reappeared. The dose of venlafaxine was decreased back to 75 mg/d. Per the Naranjo scale, the probability score for the above adverse drug reaction is 5 (probable). We discuss the published evidence of paresthesias associated with antidepressants and clinical implications for recognizing paresthesias during venlafaxine treatment that may be useful for clinicians.

Conclusion:

Clinicians need to be aware of the possible emergence of paresthesias with venlafaxine treatment, especially at doses of ≥150 mg/day. Patients who receive venlafaxine for pain disorders should be closely monitored for worsening of pain symptoms and may require adjustment of their doses.