Vol.63 No.5 September 2015
An elderly patient presenting with abnormal penciclovir blood concentration increased by famciclovir at the usual dose: a case report
1)Department of Pharmacy, Chutoen General Medical Center, 1-1 Shoubugaike, Kakegawa, Shizuoka, Japan
2)Department of Pharmacy, Kakegawa East Hospital
Abstract
Famciclovir, a prodrug of penciclovir, has been widely used as an anti-herpesvirus drug. We experienced a case of an elderly female presenting with an abnormal rise in her penciclovir blood concentration with famciclovir at the usual dose. The patient was a 91-year-old woman who was admitted to the hospital for anorexia and general fatigue. She was diagnosed as having dehydration based on the results of her blood test. We examined the medications that the patient had brought with her and records of prescribed medications in her drug notebook. We found that the patient was receiving 1,500 mg of famciclovir per day and surmised that acute renal failure was an adverse reaction of the famciclovir treatment. We proposed to the physician in charge that the patient's penciclovir blood concentration should be measured immediately and that famciclovir should be discontinued. The penciclovir blood concentration at the time of hospitalization was 20.31 μg/mL. Famciclovir is mainly excreted by the kidneys in the same manner as are other anti-herpesvirus drugs. Therefore, it is necessary to reduce the famciclovir dose and to advise the patient to drink sufficient water, when administering famciclovir to elderly patients and those with renal failure.
Key word
famciclovir, blood concentration, adverse reaction, acute renal failure
Received
May 25, 2015
Accepted
July 22, 2015
Jpn. J. Chemother. 63 (5): 469-472, 2015
