If you truly have drug induced lupus the symptoms should clear up in a short time (from what I have read it can take a few days or several months) after identifying and stopping the offending drug. Read Article here
However, some drugs can act as a trigger, not a cause of lupus, in which case you will have full flegded lupus that must be treated. Most of us will never be able to determine what triggered lupus let alone the underlying cause. Keep in mind that if you do have lupus it is not curable and the best you can hope for is remission which can be temporary or permanent.
Suggest you find a rheumatologist who is experienced with lupus. Dermatologists usually do not act as the primary physician to treat lupus.