HYDROXYCHLOROQUINE

Day 1: Reports of quinine for ‘febrile illness’ date back to 17^th century Peru; one legend is that water contaminated by cinchona tree bark was drunk and fever abated. This led to local villagers drying bark, grinding to powder and drinking to cure fever. In the early 19^th century quinine was purified from the cinchona tree bark and used to treat malaria. Synthetic forms chloroquine and #hydroxychloroquine followed in the 20^th century. Wolrd War two soldiers used chloroquine to prevent malaria and it was observed to help inflammatory arthritis

Day 2: In the 1950s, chloroquine was modified to #hydroxychloroquine to reduce toxicity; neither is routinely used for severe forms of malaria as there is high resistance. #hydroxychloroquine is licensed for adults in the UK for rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic discoid lupus erythematosus and photosensitive skin conditions. Licensed for children, but Plaquenil unlicensed for dermatological conditions

Day 2 (cont): Adult dose typically 200 or 400 mg/day (max 6.5 mg/kg ideal ideal body weight (IBW) child dose 5-6.5 mg/kg IBW max per dose 400 mg. #hydroxychloroquine is a disease-modifying anti-rheumatic drug (DMARD) and can take three or more months to work. It can be used alone or in combination other DMARDs, such as in with methotrexate for rheumatoid arthritis (RA) treatment. Can be used first line for palindromic RA and for mild systemic lupus erythematosus