Hi there. Are you currently on any kind of medication? This kind on reactions are usually due to interaction with medicines like metronidazole, disulfuraam etc.
If not then you should check the quality of alcohol you are taking. Try a more refined and expensive version.
Else simply you are allergic to alcohol.
If nothing helps i would suggest avoiding consumption of alcohol over all.
Next Steps
try taking levocitrizine 1 -2 hours before alcohol and give it a try.