Nortriptyline

1. Introduction

Nortriptyline is a tricyclic antidepressant (TCA) used to treat depression and certain off-label conditions, such as neuropathic pain and migraine prevention. It works by inhibiting the reuptake of norepinephrine and serotonin, thereby increasing their levels in the brain. It also has mild sedative properties, making it suitable for patients with insomnia related to depression.

2. Indications

  • Major depressive disorder (MDD)
  • Neuropathic pain (off-label)
  • Migraine prophylaxis (off-label)
  • Irritable bowel syndrome (IBS) (off-label)

3. Dosage

Adults:

  • Depression:
    • Starting dose: 25 mg once daily (at bedtime).
    • Maintenance dose: 50–150 mg/day in divided doses or as a single dose at bedtime.
    • Maximum dose: 150 mg/day.
  • Neuropathic pain or migraine prevention (off-label):
    • Starting dose: 10–25 mg once daily at bedtime.
    • Maintenance dose: 25–75 mg/day based on response and tolerance.

Elderly:

  • Start with 10–25 mg once daily; titrate slowly due to increased sensitivity to side effects.

Children:

  • Not recommended for children under 12 years for depression.
  • For older children, dosing is determined by weight and condition.

4. Administration

  • Take orally, with or without food.
  • Administer at bedtime if sedation occurs.
  • Avoid abrupt discontinuation to minimise withdrawal symptoms (e.g., headache, nausea, mood changes).

5. Forms Available

  • Tablets: 10 mg, 25 mg, 50 mg, 75 mg
  • Oral solution: 10 mg/5 mL

6. Side Effects

6.1 Common Side Effects:

  • Dry mouth
  • Drowsiness
  • Constipation
  • Dizziness
  • Weight gain

6.2 Less Common Side Effects:

  • Blurred vision
  • Palpitations
  • Difficulty urinating

6.3 Rare but Serious Side Effects:

  • Suicidal ideation (especially in younger patients)
  • Arrhythmias (e.g., QT prolongation)
  • Seizures
  • Serotonin syndrome (when combined with serotonergic drugs)

7. Warnings

  • Suicidal Ideation: Increased risk of suicidal thoughts and behaviours, especially in young adults under 25 years.
  • Cardiac Risk: Avoid in patients with a history of recent myocardial infarction, arrhythmias, or prolonged QT interval.
  • CNS Effects: May impair mental and physical abilities required for tasks like driving.

8. Precautions

  • Use cautiously in patients with glaucoma, urinary retention, or seizure disorders.
  • Avoid abrupt discontinuation to reduce withdrawal symptoms.
  • Monitor for worsening depression or mood changes during the initial weeks of therapy.

9. Interactions

  • Monoamine oxidase inhibitors (MAOIs): Avoid concurrent use; allow at least 14 days between stopping MAOIs and starting Nortriptyline.
  • CNS depressants (e.g., alcohol, sedatives): Increased sedation.
  • SSRIs (e.g., fluoxetine, sertraline): Risk of serotonin syndrome and increased Nortriptyline levels.
  • Anticholinergics: Enhanced anticholinergic effects (e.g., dry mouth, blurred vision, constipation).

10. Monitoring Parameters

  • Monitor therapeutic response and symptom improvement (e.g., mood, pain relief).
  • Check for signs of suicidal ideation or unusual behavioural changes, particularly in the first few weeks.
  • Monitor ECG in patients with pre-existing heart disease or those on high doses.

11. Use in Children

  • Not typically recommended for depression in children under 12 years.
  • May be used cautiously off-label for certain conditions like migraines, under specialist guidance.

12. Use in Pregnancy

  • Classified as Category C. Use only if the benefits outweigh the risks. Limited data suggest potential risks to the foetus.

13. Use in Elderly

  • Start at lower doses due to increased sensitivity to sedation, dizziness, and cardiovascular side effects.

14. Use in Kidney Disease

  • No specific dose adjustment required, as Nortriptyline is primarily metabolised by the liver.

15. Use in Liver Disease

  • Use cautiously in patients with liver impairment, as Nortriptyline is metabolised in the liver. Monitor liver function tests during treatment.

16. Patient Counselling Points

  • Take Nortriptyline at the same time each day, preferably at bedtime if it causes drowsiness.
  • Avoid alcohol, as it may increase drowsiness and other side effects.
  • Report any mood changes, suicidal thoughts, or unusual side effects to your doctor immediately.
  • Stay hydrated and consider dietary fibre or stool softeners to manage constipation.
  • Do not stop taking Nortriptyline suddenly; consult your doctor for a tapering schedule if needed.

17. Table of Brand Names, Manufacturer, and Prices in USD

Brand NameManufacturerStrength/Dosage FormPrice (USD)
PamelorMallinckrodt25 mg Tablet$20 (30 tablets)
AventylEli Lilly10 mg Capsule$15 (30 capsules)
Generic NortriptylineVarious25 mg Tablet$10 (30 tablets)

18. 15 FAQs (Frequently Asked Questions)

1. What is Nortriptyline used for?
Nortriptyline is used to treat depression, neuropathic pain, and migraines (off-label).

2. How does Nortriptyline work?
It increases norepinephrine and serotonin levels in the brain, improving mood and reducing pain perception.

3. Can Nortriptyline be used for pain?
Yes, it is effective for neuropathic pain and is often prescribed off-label for this purpose.

4. What is the usual dose of Nortriptyline?
The usual dose for depression is 50–150 mg/day, while lower doses (10–75 mg/day) are often used for pain or migraines.

5. Can Nortriptyline cause weight gain?
Yes, weight gain is a common side effect.

6. Is Nortriptyline safe during pregnancy?
It should be used cautiously during pregnancy if the benefits outweigh the risks.

7. Can Nortriptyline cause drowsiness?
Yes, drowsiness is a common side effect, especially when starting the medication.

8. Can Nortriptyline be used in children?
It is not typically recommended for children under 12 years, except in certain off-label cases.

9. How long does it take for Nortriptyline to work?
It may take 2–4 weeks for the full antidepressant effects to appear.

10. Can Nortriptyline cause dry mouth?
Yes, dry mouth is a common side effect due to its anticholinergic properties.

11. How should I stop taking Nortriptyline?
Do not stop abruptly. Consult your doctor for a tapering schedule to minimise withdrawal symptoms.

12. Can I drink alcohol while taking Nortriptyline?
No, alcohol may increase drowsiness and other side effects.

13. Can Nortriptyline be combined with other antidepressants?
It should not be combined with MAOIs or serotonergic drugs without medical guidance, as this increases the risk of serotonin syndrome.

14. Does Nortriptyline affect the heart?
Yes, it can cause arrhythmias or QT prolongation, especially in patients with pre-existing heart conditions.

15. Do I need a prescription for Nortriptyline?
Yes, Nortriptyline is a prescription-only medication.