Misoprostol is a “prostaglandin” (a chemical mediator in the body) that mediates a lot of responses in the body like producing fever, mediating pain, causing blood clots, protecting stomach from developing ulcers, etc. etc. etc.
It is hardly used coz of the unpleasant feeling / sensation including fever, burning sensation all over the body, sweating, racing of the heart (palpitation) associated with it.
It is better to avoid it all together since we have good alternatives to all the conditions for which it is needed.
Just stopping the medicine will provide relief. No need for antacids. In fact Misoprostol itself is gastric protective and had been used as adjuvant in treating gastritis/ulcer.
Health Tips
Avoid taking misoprostol for getting periods. It can produce excess flow, severe cramps, etc.