Does Amitriptyline Cause Weight Gain?
Amitriptyline (brand name Elavil) is a tricyclic antidepressant (TCA) used for depression and, at low doses, for nerve pain, migraine prevention, and sleep. Unlike many newer antidepressants, amitriptyline is one of the medications more consistently associated with weight gain. The answer here is a more definite "often, yes" — but the amount varies, and it is manageable. Here is what the references say.
The short answer
Yes — amitriptyline is one of the antidepressants more likely to cause weight gain. Drug references and Mayo Clinic list weight gain and increased appetite among its recognized side effects, and tricyclics as a class are more associated with weight gain than most SSRIs. That said, not everyone gains, the amount varies, and lifestyle steps can help limit it. MedlinePlus advises telling your doctor about unusual weight change.
What the evidence shows
Amitriptyline's prescribing information lists increased appetite and weight gain among its side effects. Mayo Clinic specifically names tricyclic antidepressants, including amitriptyline, among the antidepressants more likely to cause weight gain. The likely mechanisms include effects on histamine receptors that increase appetite, along with sedation and the general recovery of appetite as mood improves. The effect is more consistent than with most newer antidepressants, though still variable between people.
How much weight are we talking about?
References describe weight gain on amitriptyline as more likely and sometimes more noticeable than with SSRIs, but still typically gradual — commonly several pounds over months for those affected, with a wide range. Some people gain more, especially over longer-term use; others gain little. Tracking your own trend matters more than any single average figure.
Why it tends to happen
- Histamine blockade. Tricyclics block histamine receptors, which tends to increase appetite — a key reason TCAs are more linked to weight gain than SSRIs.
- Sedation. Amitriptyline is sedating; lower daytime energy can reduce activity for some people.
- Cravings for sweets and carbs. Some people report stronger cravings, which can raise intake.
- Appetite recovery. As depression eases, a suppressed appetite returns, adding to the effect.
Low-dose use for pain, migraine, or sleep
Amitriptyline is widely used at low doses (well below typical antidepressant doses) for nerve pain, migraine prevention, and insomnia. At these lower doses, the appetite and weight effect may be smaller for many people, but weight gain is still reported and worth watching. If you are taking it for pain or sleep and notice steady weight gain, your prescriber can review the dose or consider alternatives.
What you can do if you're concerned
- Track the trend, not the day. Weigh under consistent conditions and watch the multi-week pattern.
- Mind the cravings. Plan balanced meals and keep calorie-dense snacks in check if appetite rises.
- Stay active. Regular movement helps offset sedation and supports weight stability.
- Tell your prescriber early. Other medications for mood, pain, or migraine may carry less weight risk.
- Never stop on your own. Stopping abruptly can cause withdrawal and a return of symptoms.
If your goal is intentional, healthy weight management, our calorie calculator can help you understand your numbers — coordinate any plan with your clinician.
How amitriptyline compares to other antidepressants
Among antidepressants, the tricyclics (including amitriptyline) and mirtazapine are most associated with weight gain. Paroxetine (Paxil) is the SSRI most linked to gain. By contrast, bupropion (Wellbutrin) and trazodone are more weight-neutral. See the antidepressants overview and our weight-neutral options page.
When to call your doctor
Contact your doctor or pharmacist for rapid or significant weight change, changes that bother you, or any new or worsening symptoms. Seek urgent help for serious side effects described in the label or any thoughts of self-harm, which require immediate medical attention.
Frequently asked questions
- Does amitriptyline cause weight gain?
- Yes, more often than many newer antidepressants. Mayo Clinic and drug references list weight gain and increased appetite among amitriptyline's side effects, and tricyclics as a class are more associated with weight gain. Not everyone gains, and the amount varies.
- How much weight can amitriptyline cause?
- There is no single number. References describe gain as more likely than with SSRIs but still typically gradual, often several pounds over months for those affected, with a wide range. Track your own trend rather than relying on averages.
- Why does amitriptyline make you gain weight?
- Likely reasons include histamine receptor blockade that increases appetite, sedation that can lower activity, stronger cravings for some people, and the return of a normal appetite as mood improves.
- Does low-dose amitriptyline for pain or sleep cause weight gain?
- It can, though the effect may be smaller at the low doses used for nerve pain, migraine, or insomnia. Weight gain is still reported and worth watching. If you notice steady gain, your prescriber can review the dose or alternatives.
- Will I lose the weight if I stop amitriptyline?
- It varies, and you should not stop on your own. Some weight may come off after switching, but stopping abruptly can cause withdrawal and a return of symptoms. Talk to your prescriber about options if weight is a concern.
Related guides
References
Sources: MedlinePlus (NIH) — Amitriptyline · Mayo Clinic — Antidepressants and weight gain · Drugs.com — Amitriptyline · U.S. FDA — Drugs · NIMH — Depression.