Unmasking Venlafaxine-induced Orthostatic Hypotension in a Postmenopausal Woman: A Case Report on an Uncommon Adverse Effect.

Orthostatic hypotension (OH) refers to a clinically significant quick drop in blood pressure upon standing. This is due to hypovolemia, autonomic dysfunction, or adverse drug effects. Venlafaxine is a serotonin-norepinephrine reuptake inhibitor which has been typically associated with hypertension. However, several cases of OH have been reported predominantly in elderly people at higher doses. This case highlights a unique presentation of symptoms at the therauptic dose that too in a patient without conventional risk factors. A 55-year-old postmenopausal female with bipolar disorder presented with generalized weakness, dizziness, and lightheadedness a week after initiating venlafaxine for depressive symptoms. Clinical evaluation revealed significant hypotension with normal systemic, neurological, and cardiological examinations. Laboratory investigations didn't reveal anything either. The temporal association between the initiation of venlafaxine and symptom onset led to discontinuation of the drug coupled with supportive management. Symptoms resolved within 48 h, with blood pressure returning to baseline as well. Thus, this case highlights the need for clinicians to be vigilant about potential OH even at standard doses of venlafaxine in patients without typical risk factors. Hence, proving that early identification of such symptoms and prompt dose adjustment/change in therapy can mitigate complications and optimize patient outcomes.