Expert: Dr.Paul Skett - 9/17/2002

Question
Hi Paul,
For that hydralazine is under acetylation,the slow acetylator people will have more chance to get lupus-like syndrome.
However,is there any molecular interpretation given to the metabolites of hydralazine(or hydralazine itself) and the response(lupus -like syndrome)?
thanks.

Answer
Hello again, Sinn,

The mechanism of lupus from hydralazine is still unclear - most likely an autoimmune reaction - this is thought to be from the reaction of the parent compound (hydralazine itself) or one of its oxidation products with cellular components. Increase in slow acetylators is likely due, therefore, to more unchanged drug being present or more of the drug being availble for processing down the oxidation pathway.

There are a number of potential routes of drug-induced autoimmune reactions  - see:

Environmental Health Perspectives volume 107 supplement 5 pages 737-742 (1999).

Hope this helps.

Best wishes,

Paul