Famciclovir: Difference between revisions

Latest revision as of 20:38, 20 March 2026

Administration

Type: Antiviral
Dosage Forms:
Routes of Administration: Oral
Common Trade Names: Famvir

Adult Dosing

150-1000mg PO BID

Herpes zoster oticus

500mg TID x 7 days

HSV-1

500mg PO TID

Indications by Disease

Disease	Dose	Context
Herpes Simplex Virus-2	250mg PO q8hrs x 7-10 days	Initial Episode
Herpes Simplex Virus-2	125mg PO q12hrs for 5 days or 1g PO q12hrs for 1 day or 500mg PO once then 250mg PO q12hrs for 2 days	Recurrence
Herpes Simplex Virus-2	250mg PO q12hrs daily	Suppressive
Herpes gingivostomatitis	500mg PO BID x 7 days	Normal host
Herpes gingivostomatitis	500mg PO BID x 7 days	Immunocompromised
Herpes labialis	500mg PO BID x 7 days	Normal host
Herpes labialis	500mg PO BID x 7 days	Immunocompromised

Pediatric Dosing

Safety/efficacy not established

Indications by Disease

Special Populations

Pregnancy Rating: B
Lactation risk: Infant risk cannot be ruled out
Renal dosing: reduced dose
Hepatic dosing: no adjustment for mild-moderate impairment
Famvir Pregnancy Registry: 1-888-669-6682

Contraindications

Allergy to class/drug

Adverse Reactions

Serious

Neutropenia, thrombocytopenia
Skin reaction, severe
Hallucinations, delirium

Common

Nausea/vomiting, diarrhea
Headache
Fatigue
Elevated AST/ALT
Pruritus
Paresthesia
Flatulence

Pharmacology

Half-life: 2.3h
Metabolism: Hepatic, CYP450
Excretion: Mostly renal

Mechanism of Action

Inhibits DNA polymerase, selectively inhibiting herpes viral DNA synthesis and replication

Comments

References

Authors:

@@ Line 1: / Line 1: @@
-==General==
+==Administration==
-*Type: DNA polymerase inhibitor
+*Type: [[Antiviral]]
-*Dosage Forms: 125, 250, 500 PO
+*Dosage Forms:
+*Routes of Administration: Oral
 *Common Trade Names: Famvir
 ==Adult Dosing==
+*150-1000mg PO BID
+===[[Herpes zoster oticus]]===
+*500mg TID x 7 days
 ===[[HSV-1]]===
 *500mg PO TID
+===Indications by Disease===
+{{#ask: [[Has DrugName::Famciclovir]] [[Has Population::Adult]]
+ |?Treats disease=Disease
+ |?Has Dose=Dose
+ |?Has Context=Context
+ |format=table
+ |limit=50
+ |mainlabel=-
+ |headers=show
+ |sort=Treats disease
+}}
 ==Pediatric Dosing==
+''Safety/efficacy not established''
+===Indications by Disease===
+{{#ask: [[Has DrugName::Famciclovir]] [[Has Population::Pediatric]]
+ |?Treats disease=Disease
+ |?Has Dose=Dose
+ |?Has Context=Context
+ |format=table
+ |limit=50
+ |mainlabel=-
+ |headers=show
+ |sort=Treats disease
+}}
 ==Special Populations==
-*[[Drug Ratings in Pregnancy|Pregnancy Rating]]:
+*[[Drug pregnancy categories|Pregnancy Rating]]: B
-*Lactation:
+*Lactation risk: Infant risk cannot be ruled out
-*Renal Dosing
+*Renal dosing: reduced dose
-**Adult
+*Hepatic dosing: no adjustment for mild-moderate impairment
-**Pediatric
+*Famvir Pregnancy Registry: 1-888-669-6682
-*Hepatic Dosing
-**Adult
-**Pediatric
 ==Contraindications==
 *Allergy to class/drug
-*caution if renal impairment
 ==Adverse Reactions==
 ===Serious===
-*neutropenia
+*Neutropenia, thrombocytopenia
-*thrombocytopenia
+*Skin reaction, severe
-*skin rxn, severe
+*Hallucinations, delirium
-*hallucinations
-*delirium
 ===Common===
-*headache
+*Nausea/vomiting, diarrhea
-*nausea
+*Headache
-*diarrhea
+*Fatigue
-*vomiting
+*Elevated AST/ALT
-*fatigue
+*Pruritus
-*pruritus
+*Paresthesia
-*neutropenia
+*Flatulence
-*abnormal LFTs
-*paresthesia
-*flatulence
 ==Pharmacology==
-*Half-life: 2-3h
+*Half-life: 2.3h
-*Metabolism: liver, CYP450
+*Metabolism: Hepatic, CYP450
-*Excretion: urine primarily, feces
+*Excretion: Mostly renal
-*Mechanism of Action: inhibits DNA polymerase, selectively inhibiting herpes viral DNA synthesis and replication
+==Mechanism of Action==
+*Inhibits DNA polymerase, selectively inhibiting herpes viral DNA synthesis and replication
+==Comments==
 ==See Also==
+*[[Herpes simplex]]
-==Sources==
+==References==
+<references/>
-<references/>
+[[Category:Pharmacology]]
-[[Category:Drugs]]