The use of hydroxychloroquine levels can help to advance our clinical use of a medication that has been the cornerstone of lupus treatment for decades. Although the ultimate therapeutic target for hydroxychloroquine levels remains unclear, we believe that there is utility in routinely obtaining levels on at least one occasion in lupus patients. The results must be interpreted in the context of the local clinical laboratory and therapy adjusted according to the risk for undertreatment or toxicity. Additionally, the identification of nonadherent patients and attempting to improve adherence with counseling and subsequent monitoring of hydroxychloroquine levels can lead to better care of lupus patients.
On the basis of the literature available, we believe that prospectively following hydroxychloroquine levels might help avoid medication toxicity. Toxicity of hydroxychloroquine increases over time and following levels may enable appropriate surveillance and decreasing of medication dose in an effort to avoid long-term toxicity particularly after 5–10 years of exposure.
The authors wish to thank Emily Lewis for assistance in manuscript preparation.
Financial support and sponsorship
W.J.M. was supported by the Michael and Marcia Klein Professorship and Mary Piazza lupus research fund.
Curr Opin Rheumatol. 2022;34(3):151-157. © 2022 Lippincott Williams & Wilkins