Sleep aids, including melatonin or valerian, can alter drug metabolism or compound sedation. Interactions with antihypertensives, antidepressants, or insulin can lead to adverse effects like hypotension, hypoglycemia, or CNS depression. Health expert Dr Almas Fatma, explains, “Sleep pills, even the over-the-counter (OTC) ones, can clash with daily pills and cause unexpected side effects.”