The anti-malarials particularly hydroxychloroquine (brand name Plaquenil in Australia) are the cornerstone of treatment of SLE. The history of the anti-malarials is a fascinating tale of serendipity and observation.
The bark of the Cinchona tree was used as a traditional medicine in Peru for the treatment of fevers (due to Malaria) from earlier than 1600AD. The use of Cinchona bark extracted compounds for malaria, especially quinine followed from about the 19th century. After 1900, chemical derivatives of quinine – chloroquine and hydroxychloroquine became available. These have much improved tolerability compared to quinine. During WW2 patients treated for malaria with rheumatological symptoms were noted to have improvement, and clinical trials followed.
In SLE, hydroxychloroquine (HCQ) is a first line therapy. It is particularly effective for skin and joint inflammation. It has additional interesting benefits:
- Reduction in cholesterol and atheroma
- Safety in pregnancy
- Reduction in SLE flares and visceral organ disease
- Reduction in thromboembolism in the SLE associated Anti-phospholipid syndrome
HCQ is usually very safe and is well tolerated by the majority. However like any medication side-effects are possible and a minority will not tolerate SLE due to nausea for example. Rare but important side-effects include retinal toxicity and skin pigmentation. In Australia HCQ is a prescription medication and must only be taken in consultation with a medical doctor and with regular follow-up.