Hydroxychloroquine (Plaquenil) dosing: Are we following the new guidelines?

New Hydroxychloroquine Dosing

Hydroxychloroquine (Plaquenil) is an oral medication used int he treatment of several autoimmune diseases. In the field of hair loss, hydroxychloroquine is commonly used to treat lichen planopialris, frontal fibrosing alopecia, pseudopelade, discoid lupus and others.

What is the dose of Plaquenil?

Side effects of Hydroxychloroquine (Plaquenil) need to be very carefully reviewed before starting the drug. Taking the correct dose is important to reduce the overall chances of getting side effects. The optimal dose is 6.5 mg for every kg of lean body weight (not simply what the patient weighs but the lean body weight). "Lean body weight" is essentially the patients expected weight for their height and gender - it does not include the "extra" weight that some might carry. 

Instead of calculating lean body weight, newer guidelines advocate simply using the patient's true body weight and multiplying by 5 (instead of 6.5) to get the appropriate dose of Hydroxychloroquine (Plaquenil).  In our clinic we typically dose hydroxychloroquine according to the following grid:

SUMMARY and CONCLUSION

These new dosing suggestions are helpful to reduce side effects, especially the eye related side effects that can come from use of the drugs. My general feeling is that many patients I see are using slightly higher doses than in this chart.