Question: “I have a patient who is HIV positive and was recently diagnosed with psoriasis. Is phototherapy immunosuppressive?”
Answer: Although this is commonly brought up as a concern with patients that are already immunocompromised, it is also a question you might frequently be asked by other patients in light of the known increase in infection risk seen with many other biological psoriasis treatments such as cyclosporine.
First, let’s look at the history. With respect to HIV positive patients, the first serious attempts to quantify any effect of any Narrowband (~311nm) phototherapy on HIV positive patients occurred over 20 years ago in 1993. Notably, no changes in relevant blood markers or disease progression accrued with Narrowband UVB phototherapy in these early HIV positive patients, which is particularly interesting as the patients studied had phototherapy three or more years before the modern, highly active (triple-drug) antiretroviral therapy (HAART) became available.
Subsequently, Narrowband UVB has been used regularly in HIV-positive patients, both for uses in common with the general population and for treatment indications specific to HIV-positive patients, such as HIV-associated pruritic papular eruption and HIV-associated eosinophilic pustular folliculitis.
With respect to general infectious risk in healthy patients, Narrowband UVB has not been shown to increase the risk of any common infection, with the possible exception of an anecdotal association with outbreaks of preexisting cold sores (herpes simplex-1). Interestingly, a recent study of all common psoriasis treatment modalities over a cohort of 95,000 patients and subsequent herpes zoster risk showed that phototherapy did not significantly increase herpes zoster risk, while patients treated with both biologic drugs and methotrexate showed a 66% increase in risk.
If you have a question that you would like answered regarding phototherapy, Narrowband UVB or Daavlin, please email us at email@example.com or call us at 1-800-322-8546.
 Bellavista, et al. Pruritic papular eruption in HIV: a case successfully treated with NB-UVB. Dermatol Ther. 2013 Mar-Apr;26(2):173-5. doi: 10.1111/j.1529-8019.2013.01545.x.
 Misago, et al. HIV-associated eosinophilic pustular folliculitis: successful treatment of a Japanese patient with UVB phototherapy. J Dermatol. 1998 Mar;25(3):178-84.
 Shalom, et al. Systemic Therapy for Psoriasis and the Risk of Herpes Zoster. JAMA Dermatol. 2015;151(5):533-538. doi:10.1001/jamadermatol.2014.4956.