Comparative Pharmacology
Head-to-head clinical analysis: ELAVIL versus PAMELOR.
Head-to-head clinical analysis: ELAVIL versus PAMELOR.
ELAVIL vs PAMELOR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Amitriptyline inhibits the reuptake of serotonin and norepinephrine in the central nervous system, increasing their synaptic concentrations. It also exhibits anticholinergic, antihistaminergic, and alpha-adrenergic blocking effects.
Nortriptyline, the active ingredient, is a tricyclic antidepressant that inhibits the reuptake of norepinephrine and serotonin at the presynaptic neuronal membrane, increasing their availability in the synaptic cleft.
Oral: Initial 75 mg/day in divided doses or 50-100 mg at bedtime; increase to 150 mg/day; maximum 300 mg/day. IM: 20-30 mg q6h, switch to oral as soon as possible.
25-150 mg orally per day, typically as a single daily dose at bedtime or in divided doses; start at 25 mg 1-3 times daily and titrate gradually. Maximum 150 mg/day.
None Documented
None Documented
10–50 hours (mean ~20 hours); terminal elimination half-life is prolonged in elderly and patients with hepatic impairment; steady-state achieved in 7–21 days.
Mean terminal elimination half-life is 18-24 hours (range 13-40 hours) in adults; prolonged in elderly and hepatic impairment (up to 60 hours). Steady-state achieved in 4-5 days.
Renal (approximately 40% as metabolites, <5% unchanged); biliary/fecal (approximately 60% as metabolites, including glucuronide conjugates).
Primarily renal (approximately 70% as metabolites, 40-50% as glucuronide conjugates, 20-30% as free or conjugated nortriptyline; <5% unchanged), with 20-30% biliary/fecal elimination.
Category C
Category C
Tricyclic Antidepressant
Tricyclic Antidepressant