Adults

Initial dose 20 mg once daily, increasing gradually to 60 mg daily if needed, as directed by physician. Max dose typically 80 mg/day.

Elderly

Lower initial doses (e.g., 10 mg or 20 mg once daily) may be considered, with careful titration based on response and tolerability.

Renal_impairment

No dose adjustment generally required for mild to moderate renal impairment. Use with caution in severe impairment.

Onset

Initial antidepressant effects may be seen within 1-2 weeks, but full therapeutic effect typically takes 4-6 weeks.

Excretion

Excreted predominantly by the kidneys as metabolites, with a small amount excreted in feces.

Half life

Elimination half-life of Fenextine is approximately 25-30 hours. An active metabolite, Desfenextine, has a half-life of 60-70 hours.

Absorption

Well-absorbed orally, with peak plasma concentrations occurring 6-8 hours post-dose. Bioavailability is not significantly affected by food.

Metabolism

Extensively metabolized in the liver, primarily via CYP2D6 and CYP3A4 enzymes, to its active metabolite Desfenextine and other inactive metabolites.

MAOIs

Concomitant use can lead to serious, sometimes fatal, reactions including Serotonin Syndrome.

NSAIDs

Increased risk of gastrointestinal bleeding when co-administered.

Warfarin

May enhance the anticoagulant effect of warfarin, increasing bleeding risk.

Tricyclic Antidepressants (TCAs)

May increase plasma concentrations of TCAs, requiring dose adjustment.