Acute porphyria chloroquine

There have been 2 recent reports of acute porphyria developing following ingestion of chloroquine. In one case (8 -) an elderly patient treated for cutaneous porphyria tarda received 10 times the prescribed dose and suffered a severe, acute porphyric crisis as a result. The other report (9 -) referred to a 39-year-old woman who developed acute porphyria after a single dose of a combination chloroquine-primaquine tablet for malaria prophylaxis. The dose of chloroquine phosphate ingested by this patient was 300 mg. 

Hydroxychloroquine (Plaquenil), like chloroquine, is a 4-aminoquinoline derivative used for the suppressive and acute treatment of malaria. It also has been used for rheumatoid arthritis and discoid and systemic lupus erythematosus. Hydroxychloroquine has not been proved to be more effective than chloroquine. Adverse reactions associated with its use are similar to those described for chloroquine. The drug should not be used in patients with psoriasis or porphyria, since it may exacerbate these conditions. 

A severe acute flare of porphyria cutanea tarda has been reported in a 61-year-old man after 4 months of treatment with interferon alfa-2b plus ribavirin for chronic hepatitis C (553). No further relapse was observed after chloroquine treatment, despite continuation of the antiviral drugs. 

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