What is the recommended treatment with Valtrex (valacyclovir) for a pregnant woman in her second or third trimester with a history of oral herpes?

Treatment of Oral Herpes in Pregnancy with Valtrex

For pregnant women in the second or third trimester with oral herpes, valacyclovir 1 g orally twice daily for 7-10 days is recommended for acute episodes, with the same safety profile as acyclovir. 1, 2

Treatment Algorithm for Acute Oral Herpes Episodes

First-Line Treatment Options

• Valacyclovir 1 g orally twice daily for 7-10 days is the recommended treatment for first-episode herpes infection during pregnancy, including oral herpes 1, 2
• Acyclovir 400 mg orally three times daily for 7-10 days is an alternative option with equivalent safety 1, 2
• Higher doses of acyclovir (400 mg orally five times daily) were historically used for first-episode oral infection including stomatitis or pharyngitis, though it remains unclear whether oral herpes requires higher dosing than genital herpes 3

Safety Profile in Pregnancy

• Current CDC registry findings provide reassurance that there is no increased risk for major birth defects after acyclovir or valacyclovir treatment compared with the general population 1, 2
• No consistent pattern of adverse pregnancy outcomes has been reported after acyclovir or valacyclovir exposure 1
• Both medications are considered safe throughout pregnancy, including the second and third trimesters 1, 2

Suppressive Therapy Considerations

When to Consider Suppression

• For pregnant women with frequent, severe recurrences of oral herpes, suppressive prophylaxis may be indicated starting at 36 weeks gestation 3, 4
• Suppressive therapy with valacyclovir 1000 mg orally twice daily or acyclovir 400 mg orally three times daily can be initiated at 36 weeks and continued until delivery 2, 4

Important Distinction: Oral vs. Genital Herpes

• While suppressive therapy at 36 weeks is strongly recommended for women with genital herpes to prevent neonatal transmission (which carries a 30-50% risk with primary infection near delivery), the indication for oral herpes suppression is less clear 2, 4
• The primary concern with genital herpes is vertical transmission during vaginal delivery, which does not apply to oral herpes 2
• Suppression for oral herpes should be reserved for women with particularly frequent or severe recurrences that significantly impact quality of life 3

Special Populations

Immunocompromised Pregnant Women

• HIV-infected pregnant women have the same safety profile for valacyclovir 1
• Immunocompromised patients may require higher doses of acyclovir (400 mg orally three to five times daily) 1, 2
• If lesions persist during standard acyclovir treatment, acyclovir resistance should be suspected and alternative therapy considered 1, 2

Life-Threatening Maternal HSV Infection

• For disseminated HSV infection, encephalitis, pneumonitis, or hepatitis, intravenous acyclovir 5 mg/kg every 8 hours is definitively indicated, as benefits clearly outweigh any theoretical risks 1, 2

Common Pitfalls to Avoid

• Do not use topical acyclovir therapy - it is substantially less effective than systemic treatment and its use is discouraged 3
• Do not assume that oral herpes requires different dosing than genital herpes unless dealing with severe stomatitis or pharyngitis 3
• Do not withhold treatment due to pregnancy concerns - the safety data for both acyclovir and valacyclovir in pregnancy is reassuring 1, 2
• Do not routinely prescribe suppressive therapy for oral herpes unless recurrences are frequent and severe, as the primary indication for suppression at 36 weeks relates to preventing neonatal transmission from genital herpes 2, 4

Counseling Points

• Patients should be informed about the chronic nature of HSV infection with potential for recurrent episodes 3
• Women should be advised to avoid oral-genital contact during active oral herpes outbreaks to prevent transmission to partners 2
• Patients should inform all healthcare providers about their HSV infection 1
• The risk of transmission to the neonate from oral herpes is primarily through postnatal contact rather than during delivery 2