Inhibits viral DNA polymerase, preventing viral replication.
Available Quantities
125 mg, 250 mg, 500 mg tablets
Dosage/Instructions
HSV: Take 1 500 mg tablet 3 times daily for 7 days
HZV: Take 1 250 mg tablet 3 times daily for 7 days
Safety Info for Famvir®
Pregnancy & Nursing
Limited data; use with caution
Pediatric Use
No studies
Contraindications, side effects, etc.
Contraindications: Hypersensitivity to famciclovir or penciclovir cream. Common Side Effects: Headache, nausea; gastrointestinal effects (diarrhea, abdominal pain, vomiting); less common effects include confusion, mood changes, rash, pruritus. Acute renal failure reported in patients with underlying renal disease receiving high doses. Dosage adjustments are necessary in patients with renal impairment.
Inhibits viral DNA polymerase, preventing viral replication.
Available Quantities
500 mg, 1000 mg tablets
Dosage/Instructions
HSV: Take 1 1000 mg tablet 3 times daily for 7 days
HZV: Take 1 500 mg tablet 3 times daily for 7 days
Safety Info for Valtrex®
Pregnancy & Nursing
Limited data; use with caution
Pediatric Use
No studies
Contraindications, side effects, etc.
Contraindications: Allergy to valacyclovir or acyclovir. Common Side Effects: Nausea, stomach pain, headache. Serious side effects can include allergic reactions, kidney problems, and effects on red blood cells like fever, easy bruising or bleeding, pale skin. It may harm the kidneys, especially when used with other medicines that can harm the kidneys. Patients with HIV/AIDS, kidney disease, or those who have had a kidney or bone marrow transplant should use it with caution.
Inhibits viral DNA polymerase, preventing viral replication.
Available Quantities
7.5 ml
Dosage/Instructions
Instill 1 drop to the affected eye every 2 hours, up to 9 drops per day, until the corneal ulcer heals. Post-healing, reduce to 1 drop every 4 hours for 7 more days. Seek alternative treatments if no improvement in 7 days or if healing isn’t complete in 14 days. Do not use trifluridine for over 21 days to avoid eye toxicity.
Safety Info for Viroptic®
Pregnancy & Nursing
Limited data; use with caution
Pediatric Use
≥6 years
Contraindications, side effects, etc.
Contraindications: Known hypersensitivity to trifluridine or any component of the formulation.
Warnings/Precautions: Use with caution in patients with a history of hypersensitivity to other antiviral agents. Avoid prolonged use as it may lead to ocular toxicity. Not for systemic, intravitreal, or injection use.
Common Side Effects: Transient stinging or burning upon application, palpebral edema, hyperemia (redness of the eye), punctate keratitis, and rarely, allergic reactions.
Inhibits viral DNA polymerase, preventing viral replication.
Available Quantities
5 g
Dosage/Instructions
Instill 1 drop in the affected eye 5 times per day (approximately every 3 hours while awake) until the corneal ulcer heals, and then 1 drop 3 times per day for 7 days.
Safety Info for Zirgan®
Pregnancy & Nursing
Limited data; use with caution
Pediatric Use
≥2 years
Contraindications, side effects, etc.
Contraindications: Hypersensitivity to ganciclovir or any component of the gel.
Warnings/Precautions: Caution in patients with known hypersensitivity to acyclovir or valacyclovir as cross-reactivity may occur. Not for injection into the eye, or for oral or intravenous use.
Common Side Effects: Blurred vision, eye irritation, increased tearing, and eye redness. Less common effects include eye pain, foreign body sensation in the eye, and hypersensitivity reactions.
Inhibits viral DNA polymerase, preventing viral replication.
Available Quantities
200 mg, 400 mg, 800 mg tablets
Dosage/Instructions
HSV: Take 1 800 mg tablet 5 times daily for 7 days
HZV: Take 1 400 mg tablet 5 times daily for 7 days
Safety Info for Zovirax®
Pregnancy & Nursing
Limited data; use with caution
Pediatric Use
≥2 years
Contraindications, side effects, etc.
Contraindications: Known hypersensitivity to acyclovir, valacyclovir, or any component of the formulation.
Warnings/Precautions: Caution in patients with renal impairment as dosage adjustment may be necessary. Care should be taken to maintain adequate hydration in patients receiving high doses.
Common Side Effects: For oral or IV forms: Nausea, vomiting, diarrhea, headache, and in some cases, reversible renal dysfunction, and neurologic symptoms. For topical cream/ointment: Local skin reactions including mild pain, burning, or itching.