TABLE 7-2.

Antiviral Drugs Used for Treatment of Feline Herpesvirus Infections

Drug	Dose	Interval	Route	Comments
Famciclovir	62.5 mg/cat, 125 mg/cat, or 40-90 mg/kg	q8h	PO	Reduce dose for cats with renal insufficiency. Compound suspensions are bitter and poorly tolerated. Broken tablets are best administered in a gel cap. Safe in kittens.
Cidofovir	0.5% solution	q12h	Topical ophthalmic	Monitor for ocular irritation. Solution prepared from commercial 7.5% intravenous solution by dilution in sterile saline. Store diluted solution up to 6 months at 4°C, −20°C, and −80°C. Can also be obtained from compounding pharmacies.
Idoxuridine	0.1% solution or 0.5% ointment	5-6 times daily	Topical ophthalmic	Monitor for ocular irritation and ulceration. Compounding may be required.
Trifluridine	1% solution	5-6 times daily	Topical ophthalmic	May be poorly tolerated.
Vidarabine	3% ointment	5-6 times daily	Topical ophthalmic	Well tolerated. Compounding may be required.
Lysine	250 mg (kittens) 500 mg (cats)	q12h	PO	Questionable efficacy. Bolus administration preferred to dietary supplementation.
Zidovudine	5 to 15	q12h	PO, SC	Monitor CBC weekly during treatment for the first month, then monthly. Use low end of the dose range in renal failure. Use higher dose with caution.