Is it dangerous to use social drugs while having epilepsy?

Yes: Assuming you mean illegal substances, then the answer is yes, ... Dangerous for the general public and even more so in someone with an underlying medical condition such as a seizure disorder.

AVOID IT TOTALLY: Tendency to experience seizure is always present and many events can drop protective threshold. Recreational drugs are notorious, as maybe also alcohol in some cases. Drugs such as cocaine, amphetamines, speed, are critically risky and life-threatening. Social drugs, whatever that implies, should be totally avoided unless you have a "death wish". Talk to your doctor about this.