What amitriptyline is used for (common use)
Amitriptyline is a tricyclic antidepressant (TCA) approved for major depressive disorder. Clinicians also prescribe it off-label for several chronic pain conditions because of its analgesic and sleep-promoting properties. These include neuropathic pain (such as diabetic neuropathy and postherpetic neuralgia), migraine prevention, fibromyalgia, temporomandibular joint disorder, irritable bowel syndrome, interstitial cystitis, and tension-type headache. Its multipronged mechanisms—serotonin/norepinephrine reuptake inhibition and antihistamine effects—can improve sleep continuity, mood, and pain thresholds.
Symptom relief timelines vary. For depression, noticeable mood improvement may take 2–4 weeks, with full response often requiring 6–8 weeks at a therapeutic dose. For neuropathic pain and migraine prophylaxis, some patients notice benefits within 1–2 weeks after reaching an effective dose, though several weeks may be needed for optimal effect. Because sedation is common, bedtime dosing is typical and can be useful for patients with comorbid insomnia.
Amitriptyline dosage and directions
Start low and go slow is the rule for amitriptyline dosing. For depression, clinicians often initiate 25–50 mg at bedtime or divided doses, increasing by 25–50 mg every few days as tolerated. Usual maintenance falls between 75–150 mg/day; some patients may require up to 200 mg/day under close supervision. Older adults typically start at 10–25 mg nightly due to heightened sensitivity to anticholinergic and cardiac effects.
For neuropathic pain, migraine prevention, and other off-label indications, lower doses are often effective. A common regimen begins at 10–25 mg at night, titrating by 10–25 mg increments every 3–7 days to a typical range of 25–75 mg nightly. Using the lowest effective dose minimizes daytime drowsiness, dry mouth, constipation, and dizziness. If sedation is excessive, dose reductions or earlier evening timing may help.
Take amitriptyline consistently, preferably at bedtime with or without food. Do not crush or chew tablets. If a dose is missed, follow the missed-dose advice below. Do not abruptly stop; tapering over weeks helps prevent discontinuation symptoms such as nausea, headache, sleep disturbance, irritability, and flu-like feelings. Always individualize dosing with your prescriber, particularly when switching from or to other antidepressants (to avoid interactions and serotonin syndrome risk).
Precautions and monitoring
Amitriptyline carries a boxed warning for increased risk of suicidal thoughts and behaviors in children, adolescents, and young adults, especially early in treatment or during dose changes. Monitor mood, behavior, and sleep closely, and seek prompt medical attention for new or worsening depression, agitation, or suicidal thinking. Older adults are more susceptible to confusion, falls, anticholinergic effects, and cardiac conduction issues; conservative dosing and fall-prevention strategies are advised.
Cardiac safety matters. TCAs can prolong PR, QRS, and QT intervals. Patients with known cardiovascular disease, arrhythmias, or electrolyte disturbances may need baseline and follow-up ECGs, particularly at higher doses. Avoid dehydration and correct low potassium or magnesium to reduce arrhythmia risk. Use caution in glaucoma (especially angle-closure), urinary retention or BPH, severe constipation, seizure disorders, thyroid disease, and liver impairment. Alcohol and other sedatives can intensify drowsiness and impair coordination. Photosensitivity has been reported—consider sun protection if you notice heightened sensitivity.
Contraindications
Do not use amitriptyline if you have hypersensitivity to TCAs, recent myocardial infarction, or are currently taking monoamine oxidase inhibitors (MAOIs) or within 14 days of MAOI use (including linezolid or IV methylene blue) due to risk of severe interactions and hypertensive crisis. It is contraindicated in acute recovery after MI and should be avoided in uncontrolled narrow-angle glaucoma and severe urinary retention. Use extreme caution—or consider alternatives—if there is a history of significant arrhythmias or prolonged QT interval.
Possible amitriptyline side effects
Common side effects reflect anticholinergic and antihistamine properties: dry mouth, constipation, blurred vision, urinary hesitancy, drowsiness, dizziness, increased appetite, and weight gain. Orthostatic hypotension can cause lightheadedness or fainting when standing; rise slowly and stay hydrated. Daytime grogginess often improves with dose adjustments or earlier evening dosing. Chewing sugar-free gum, fiber supplementation, and hydration can help mitigate dryness and constipation.
Less common but important effects include confusion (especially in older adults), sweating, tremor, sexual dysfunction, and photosensitivity. TCAs can affect conduction and heart rhythm; seek care for palpitations, syncope, chest pain, or shortness of breath. Rare but serious events include angle-closure glaucoma, significant urinary retention, seizures, severe constipation/ileus, and hepatotoxicity (watch for dark urine, jaundice, right upper quadrant pain).
Serotonin syndrome may occur when combined with other serotonergic agents. Warning signs include agitation, confusion, fever, sweating, rapid heart rate, tremor, muscle rigidity, and diarrhea—seek emergency medical attention if suspected. Report any persistent or bothersome adverse effects to your healthcare professional; dose changes or alternative therapies may be appropriate.
Amitriptyline drug interactions
Avoid MAOIs and allow a 14-day washout. Combining amitriptyline with other serotonergic drugs (SSRIs such as fluoxetine, sertraline; SNRIs; tramadol; linezolid; triptans; St. John’s wort) can increase serotonin syndrome risk. Many SSRIs and bupropion inhibit CYP2D6, potentially raising amitriptyline levels and side effects; fluoxetine and paroxetine are notable. If combinations are necessary, clinicians often lower the TCA dose and monitor closely.
Additive sedation occurs with alcohol, benzodiazepines, opioids, sedating antihistamines, and sleep medications. Anticholinergic burden increases with drugs like oxybutynin, benztropine, or first-generation antihistamines, raising risks of constipation, confusion, and urinary retention. Medications that prolong QT interval (certain antipsychotics, macrolide antibiotics, methadone, and some antiarrhythmics) may compound cardiac risk—consider ECG monitoring and alternatives when possible.
Cimetidine can elevate TCA concentrations; consider dose adjustments. Carbamazepine may lower TCA levels. Blood pressure agents may have altered effects due to TCA-induced norepinephrine reuptake blockade. Always provide your prescriber and pharmacist a complete medication and supplement list to screen for interactions proactively.
Missed dose
If you take amitriptyline once nightly and miss a dose, take it when remembered unless it is close to your usual wake time; if so, skip the missed dose and resume the regular schedule that evening. Do not double doses. For multiple-daily dosing, take the missed dose when remembered unless it’s almost time for the next dose—then skip it. Consistent timing helps maintain effectiveness and reduce side effects.
Overdose: what to know
Amitriptyline overdose is a medical emergency. Symptoms include extreme drowsiness, confusion, agitation, seizures, rapid or irregular heartbeat, low blood pressure, widened QRS on ECG, fever, dilated pupils, and severe anticholinergic signs (very dry mouth, flushed skin, urinary retention). If overdose is suspected, call emergency services or Poison Control (1-800-222-1222 in the U.S.) immediately. Do not induce vomiting unless instructed by medical professionals. Hospital care may include cardiac monitoring, airway support, and IV sodium bicarbonate to treat cardiotoxicity.
Storage and handling
Store amitriptyline tablets at 68–77°F (20–25°C) in a dry place away from light and moisture. Keep in the original, child-resistant container and out of reach of children and pets. Do not use after the expiration date. For safe disposal, use take-back programs or follow FDA guidance on medication disposal; do not flush unless specifically instructed.
Special populations: pregnancy, breastfeeding, and older adults
During pregnancy, amitriptyline may be considered when benefits outweigh risks; discuss family-planning and treatment goals with your clinician. Late-pregnancy exposure may lead to transient neonatal symptoms (jitteriness, feeding problems). In breastfeeding, small amounts appear in milk—monitor infants for excessive sleepiness or poor feeding. In older adults, prioritize the lowest effective dose, watch for cognitive changes, constipation, urinary retention, falls, and cardiac effects, and regularly review medications to reduce anticholinergic burden.
Practical tips to improve tolerability
Start at night to leverage sedation, and titrate slowly. Manage dry mouth with water, sugar-free gum, or saliva substitutes; constipation with fiber, fluids, and activity; and dizziness by rising slowly. Limit alcohol and avoid combining with other sedatives. Consider periodic weight and blood pressure checks. If you experience persistent daytime drowsiness, ask about earlier evening dosing or dose reduction. Never stop abruptly—plan a taper with your prescriber.
U.S. sale and prescription policy: can you buy amitriptyline without prescription?
In the United States, amitriptyline is a prescription-only medication. Federal and state laws require a valid prescription from a licensed clinician to dispense it. Buying or selling prescription medicines without a prescription is illegal and unsafe. Avoid online pharmacies that offer amitriptyline without a prescription—they may be counterfeit, subpotent, contaminated, or dangerous. For legal, safe access, use licensed pharmacies and consider telehealth appointments, where a clinician can evaluate your condition and, when appropriate, prescribe amitriptyline.
Health systems and rehabilitation networks can provide structured, lawful care pathways that include evaluation, monitoring, and prescriptions when clinically appropriate; however, there is no legitimate program in the U.S. that dispenses amitriptyline without a valid prescription. To keep costs down, ask about generics, 90-day supplies, mail-order options, and pharmacy savings programs. Verify online pharmacies through the National Association of Boards of Pharmacy (look for .pharmacy or NABP accreditation) to ensure you are using a credible, compliant source.
