Hydroxychloroquine and Shingles Healing Response
Hydroxychloroquine does not directly impair the healing of herpes zoster (shingles) rash, but it increases the risk of developing shingles in the first place, particularly in patients with autoimmune conditions. The primary concern is prevention rather than healing impairment once infection occurs.
Risk of Developing Shingles
Hydroxychloroquine is associated with an increased risk of herpes zoster reactivation in patients with rheumatic diseases:
- Hydroxychloroquine increases the risk of herpes zoster by approximately 1.4 to 2-fold compared to non-users in patients with rheumatic diseases 1, 2.
- In a large Asian cohort study, hydroxychloroquine use was associated with an adjusted odds ratio of 1.95 (95% CI 1.39-2.73) for developing herpes zoster in rheumatoid arthritis patients 3.
- A prospective study found hydroxychloroquine use independently associated with herpes zoster infection, with the risk increasing with higher doses 2.
- Chloroquine diphosphate (a related antimalarial) was identified as a specific risk factor for herpes zoster in dermatomyositis/polymyositis patients 4.
Treatment of Shingles in Immunocompromised Patients
When shingles does occur in patients taking hydroxychloroquine, standard antiviral therapy remains effective:
- High-dose IV acyclovir remains the treatment of choice for VZV infections in immunocompromised hosts 5.
- For uncomplicated herpes zoster, oral acyclovir or valacyclovir should be used at least until all lesions have scabbed 5.
- Immunocompromised patients may experience prolonged lesion development (7-14 days) and slower healing unless effective antiviral therapy is administered 5.
- Without adequate treatment, some immunosuppressed patients develop chronic ulcerations with persistent viral replication complicated by secondary bacterial and fungal superinfection 5.
Management Considerations
For patients on hydroxychloroquine who develop shingles:
- Initiate appropriate antiviral therapy immediately (oral acyclovir, valacyclovir, or famciclovir for uncomplicated cases; IV acyclovir for disseminated or severe disease) 5.
- Consider temporary reduction in immunosuppressive medication for disseminated or invasive herpes zoster 5.
- Continue antiviral treatment at least until all lesions have scabbed 5.
- Monitor for complications including postherpetic neuralgia, which occurred in 58.3% of dermatomyositis/polymyositis patients with herpes zoster 4.
Prevention Strategies
Given the increased risk, preventive measures are critical:
- Patients with rheumatic diseases on hydroxychloroquine should be encouraged to receive herpes zoster vaccination 2.
- The recombinant zoster vaccine (RZV) is recommended for adults aged 50 years and older, particularly those on immunosuppressive therapy 6.
- Consider antiviral prophylaxis in high-risk situations, though routine prophylaxis is not standard for hydroxychloroquine alone 5.
Important Caveats
- The increased risk of herpes zoster is dose-dependent for hydroxychloroquine 2.
- Combination therapy with other immunosuppressants (particularly corticosteroids ≥10 mg/day, biologics, or methotrexate) further increases herpes zoster risk 3, 1.
- Hydroxychloroquine itself does not have direct antiviral activity against varicella-zoster virus, despite having demonstrated in vitro activity against some RNA viruses 5.