Dosing
CrCl > 80: 100 mg q 12 h.
CrCl 80-50: 100 mg q 24 h.
CrCl 50-10: 0.1 - 0.2 g 2-3 x wk.
CrCl < 10: 0.1 - 0.2 g q wk.
Hemodialysis: not known.
Peritoneal dialysis: ? unknown.
Important side effects
Confusion and a wide variety of neurological complications, especially in the elderly.
Important drug interactions
Coadministration of amantadine and trimethoprim (alone or in combination with sulfamethoxazole) can lead to reduced tubular secretion of both amantadine and trimethoprim.
Rants and Screeds
A drug of historical interest for influenza.
Pearls
Chinese poultry farmers used amantadine to protect birds from avian flu. Chinese chicken was given an estimated 2.6 billion doses of amantadine. And the result? Avian flu (H5N1) in China and Southeast Asia are now resistant to amantadine (PubMed).
Use(d) for
Influenza A (100% of influenza is now resistant to amantadine and rimantadine; use zanamivir or oseltamivir).
Don't use for
Influenza B. Not B. Got that? Not B.
Class
M2 pump inhibitor that prevents viral uncoating.
Last Update: 04/03/19.