Foscarnet

Administration

• Type: Antiviral
• Dosage Forms:
• Routes of Administration: IV
• Common Trade Names: Foscavir

Adult Dosing

Indications by Disease

Disease	Dose	Context
CMV colitis	90mg/kg IV q12hrs x 21 days	Until symptom resolution
CMV neurologic disease	90mg/kg IV q12hrs x 21 days then 90-120mg/kg IV q24hrs	Combined with Ganciclovir
Encephalitis	90mg/kg IV every 12 hrs	CMV

Special Populations

• Pregnancy Rating: C
• Lactation risk: Infant risk cannot be ruled out
• Renal dosing: Complicated dose adjustment required!
• Hepatic dosing: No adjustement

Contraindications

• Allergy to class/drug

Adverse Reactions

Serious

• Hyperphosphatemia, hypophosphatemia, hypocalcemia, hypokalemia, hypomagnesemia
• Pancreatitis
• Pancytopenia
• Renal failure, renal impairment
• Seizure

Common

• Nausea, vomiting, diarrhea
• Anemia, granulocytopenic disorder
• Headache
• Fever

Pharmacology

• Half-life: 3.3-4h
• Metabolism:
• Excretion: Renal

Mechanism of Action

• inhibits pyrophosphate binding on viral DNA polymerases

See Also

• CMV
• HSV
• Immunocompromised antibiotics