Hello and welcome to Healthcare Magic. Thanks for your query.
It is unlikely that being breast-fed by a heroin
addict would have had any major or permanent impact on your health. Moreover, it is unclear whether your cousin was actively using heroin at the time of breast feeding you. Even if this was the case, iv heroin has a short duration of action and it is less likely that significant amounts of the drug would have been present in the breast milk.
However, if you take heroin, it is going to put you at risk for various health consequences. It is good that you have quit this habit. I would advise you to remain clean never to restart the habit.
Wish you all the best.
Dr. Jonas Sundarakumar