Moderate
Amitriptyline × Tamsulosin
Tricyclic antidepressants (TCA)×Alpha-adrenergic blockers for prostatic disorders
Mechanism
Additive orthostatic hypotension. Both block α1-adrenoceptors: tamsulosin selectively (for the prostate), amitriptyline systemically. Effects add up.
Symptoms
Postural dizziness, syncope, fatigue. Older patients: fall and fracture risk.
Management
On the combination, begin amitriptyline at 10 mg at bedtime. In older patients, do not exceed 25 mg/day. Take tamsulosin in the evening. Check standing/sitting BP at 1–2 weeks. For neuropathic pain, alternatives: gabapentin or pregabalin.