Ask your doctor before using ethanol together with ivermectin 12. Using ethanol with ivermectin can increase the blood levels or add to the side effects of ivermectin. This can cause skin rash, swelling, headache, dizziness, weakness, nausea, vomiting, diarrhoea, stomach pain, seizure (convulsions), shortness of breath, and numbness or tingling. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.