One to two weeks for most start-up effects: the NHS says it for antidepressants - most ease after a couple of weeks as your body adjusts - and the arc holds for blood pressure drugs and metformin too.
Three shapes: the fading arc (worst week one, gone by week three - the commonest); the persistent flat line (steady past a month is a dose or drug mismatch - adjust or switch, not endure); and the late arrival (omeprazole's magnesium dip past 3 months, statin aches weeks to months in) - new symptoms on an old drug still deserve mention. The absolute: anything looking like allergy - lip, tongue, or throat swelling, hives with breathing trouble - is an emergency, never a wait-it-out. Pymander is a free AI doctor, 24/7 by text, and can help you classify yours.
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Common questions
How long do medication side effects last?
Most start-up side effects are a one-to-two-week story. The NHS says it for sertraline and escitalopram - most side effects ease after a couple of weeks as your body gets used to the medicine - and the same arc holds across blood pressure drugs (lisinopril's early dizziness), metformin (the famous first-weeks stomach upset), and statins. The pattern exists because your body adapts: receptors adjust, fluid balances reset, enzyme systems recalibrate. Three shapes to recognize. The fading arc: worst in week one, gone by week three - the commonest, and the reason doctors say give it two weeks. The persistent flat line: side effects that hold steady past a month are not start-up effects - they are a dose or drug mismatch, and the answer is adjust or switch, not endure: say it out loud. The late arrival: some effects only show after months - omeprazole's magnesium dip past 3 months, statin muscle aches weeks to months in - which is why new symptoms on an old drug still deserve a mention. The one absolute: a side effect that looks like an allergic reaction - swelling of lips, tongue, or throat, hives with breathing trouble - is never a wait-two-weeks effect; it is an emergency. Pymander is a free AI doctor, 24/7 by text, that can help you classify what you are feeling.