Amitriptyline Side Effects: What to Expect and How to Manage

If you're starting amitriptyline or helping someone who is, you probably want a straight-up list of what can happen and what to do. Amitriptyline is an older antidepressant (a tricyclic) that can help mood, pain, and sleep—but it brings side effects that are worth knowing before you start.

Common, day-to-day side effects

Expect some effects in the first days to weeks. The most common are dry mouth, drowsiness, constipation, blurred vision, and weight gain. Many people feel sleepy or groggy at first; taking the dose at night often helps. Dry mouth is annoying but can be eased with sugar-free gum, sips of water, or saliva substitutes. Constipation responds to more fiber, fluids, and gentle laxatives if needed.

Other frequent effects include dizziness (especially when standing up), mild tachycardia (fast heart rate), and trouble urinating. If you're older, confusion and falls are more likely—so start low and go slow with doses.

Serious side effects and when to get help

Some reactions need immediate medical attention. Tell your provider or go to the ER if you have chest pain, fainting, fast irregular heartbeats, severe lightheadedness, seizures, high fever with stiff muscles, or a sudden rash. Amitriptyline can affect the heart’s electrical rhythm (QT prolongation) and raise the risk of dangerous arrhythmias—this is more likely at high doses or with other heart medicines.

Watch for worsening depression or suicidal thoughts, especially in people under 25. Also be alert for signs of serotonin syndrome if amitriptyline is combined with an SSRI, SNRI, MAOI, or certain migraine meds: high fever, confusion, tremor, and fast reflexes. That’s an emergency.

Interactions matter. Avoid MAO inhibitors and be cautious with other sedatives, alcohol, antihistamines, anticholinergic drugs, and some heart drugs. Let every prescriber and pharmacist know you take amitriptyline so they can check interactions.

Before starting, your doctor may request an ECG if you’re over 40, have heart disease, or take other meds that affect the heart. Electrolyte checks (potassium, magnesium) can help if you’re on diuretics, because low levels increase the risk of arrhythmia.

Tapering off should be gradual. Stopping suddenly can cause withdrawal-like symptoms: anxiety, sleep problems, sweating, nausea, and flu-like feelings. Work with your prescriber to reduce the dose slowly over weeks.

Practical tips: take it at night if drowsy, avoid alcohol and driving until you know how it affects you, report persistent weight gain or sexual problems, and keep a simple symptom diary for the first month. If side effects are strong, lower the dose or switch to another medication with your doctor’s help.

Want specific advice for your situation? Talk to your prescriber or pharmacist—they can tailor monitoring and choices to your age, heart history, and other meds. Knowing what to watch for makes amitriptyline safer and more usable for daily life.