Does illegal substance abuse void health insurance?

During an hospital visit, blood/ urine test confirms illegal substances.Can insurance withhold payment for other services or rescind policy?

If it's pre-existing, yes but you would have known that prior to the coverage being bound. Most policies actually cover substance abuse treatment.
No, they cannot withhold payments for a hospital visit. Source(s): Insurance Agent

I don't think so, but I am not certain. It may boil down to what you are being treated for. I work for a psychiatrist who specializing in addictionology (also in Eating Disorders and severe psychiatric disorders[bipolar/schizphrenia... - he treats patients in a rehab facility and insurance pays for their stays.
The insurance carrier could refuse coverage or require you be checked in for treatment for an addiction.
I don't believe so. I'm not 100% positive, though. But about 95%. Not that it does you any good. SOME of that will depend on what state you are in, but I've never seen a state that allows health companies to void or cancel policies for illegal substances.

If, however, you should try to get a new policy, or change your plan, you're going to have a REALLY hard time.
agent, 21+ years
I think not as most insurance policies pay for detox, but you will have to check your specific policy..