Hydroxychloroquine: 2 months to onset

How long does it take for hydroxychloroquine to start working?

Hydroxychloroquine (Plaquenil) is a notoriously slow acting drug. It is frequently used for treating scarring alopecia. It can take 2 months or more before the drug really starts to have an effect and actually help a patient using the drug. Because the drug is so delayed in its onset, I usually give it 4-6 months before judging if it is working ... and sometimes even longer. Clinical symptoms (itching and burning) are reduced first in those who respond followed by clinical signs (perifollicular erythema, perifollicular scale, scalp erythema). The reduction or slowing of hair loss is last.

Hydroxychloroquine is the slowest acting of all the typical oral immunomodulators such as doxycycline, methotrexate, mycophenolate and cyclosporine (cyclosporine tends to be the most rapid). For my patients I often tell them we are going to start the “timer” in 2 months. So if I see them in July, I tell them we will actually set your zero point or start of treatment in September. I tell the patient that for the next two months they can 'consider/imagine' that they are not really even on treatment from the perspective of their scalp. (Of course blood tests need to be done because the body knows from day 1 that the drug was taken.

I may even ask patients to come in at month 2 or 3 for repeat photos (or have them take at home) as a reminder that this time point is really the starting point.