Contraindications Famvir famciclovir is contraindicated in patients with known hypersensitivity to the product, its components, and Denavir penciclovir cream. Genital herpes can also be transmitted in the absence of symptoms through asymptomatic viral shedding. Doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for it. As genital herpes is sexually transmitted disease, patients should avoid contact with lesions or intercourse when lesions and famvir ostaa turskaa or symptoms are present to avoid infecting partners. Penciclovir caused an increased incidence of micronuclei in mouse bone marrow in vivo when administered intravenously at doses highly toxic to bone marrow 500 mg kg but not when administered orally. Printer-Friendly Format Email to Friend Suggested Reading by Our Doctors acyclovir, Zovirax Explains the medication acyclovir Zovirax drug used to treat initial genital herpes infections and to treat patients with recurrent severe genital herpes.