Nortriptyline (Nortriptyline Hydrochloride)

Nortriptyline is a tricyclic antidepressant used to treat several mood and pain disorders.

• Major depressive disorder: alleviates depressive symptoms by improving mood, sleep, and concentration in adult patients.
• Depressive episodes associated with bipolar disorder: helps stabilize mood during depressive phases when used under specialist supervision.
• Chronic neuropathic pain: reduces pain intensity and improves functional ability in patients with nerve‑related pain conditions.
• Migraine prophylaxis: decreases frequency and severity of migraine attacks when taken regularly as preventive therapy.

• Nortriptyline inhibits the reuptake of norepinephrine and serotonin, increasing their synaptic concentrations. It also antagonizes muscarinic, histamine H1, and alpha‑adrenergic receptors, contributing to its analgesic and sedative properties while influencing central nervous system neurotransmission.

Nortriptyline may cause a range of adverse reactions, which vary in frequency and severity.

Common Side Effects

• Dry mouth: reduced salivation leading to discomfort.
• Constipation: slowed gastrointestinal motility.
• Drowsiness or fatigue: increased sedation, especially at treatment initiation.
• Weight gain: modest increase in appetite and body weight.

Serious or Rare Side Effects

• Cardiac arrhythmias: potential conduction abnormalities, particularly in patients with pre‑existing heart disease.
• Seizures: lowered seizure threshold, especially at high doses.
• Severe hypotension: abrupt drop in blood pressure upon standing.
• Hepatotoxicity: rare liver enzyme elevations requiring monitoring.

Before initiating therapy, clinicians should evaluate patient history and monitor for specific risks.

• Cardiac assessment: obtain baseline ECG in patients with known heart disease.
• Concomitant CNS depressants: avoid or adjust dose when combined with alcohol or sedatives.
• Elderly patients: start with lower doses and monitor for anticholinergic effects.
• Suicide risk: monitor mood changes closely during early treatment phases.
• Store at ambient temperature: keep below 25°C in the original packaging, protect from moisture and direct sunlight.

Nortriptyline can interact with several drug classes, requiring careful management.

Major Interactions (Avoid)

• Monoamine oxidase inhibitors (MAOIs): risk of hypertensive crisis and serotonin syndrome; a 14‑day washout is required.
• CYP2D6 inhibitors (e.g., fluoxetine, paroxetine): can markedly increase nortriptyline plasma levels, leading to toxicity.

Moderate Interactions (Monitor Closely)

• Anticholinergic agents: additive dry mouth, constipation, and urinary retention.
• CNS depressants (benzodiazepines, opioids): enhanced sedation and respiratory depression.
• Diuretics: may potentiate orthostatic hypotension.
• NSAIDs and anticoagulants: increased risk of gastrointestinal bleeding.