Although there is no direct interaction between alcohol and Tecfidera (dimethyl fumarate), you should not drink excessive quantities of alcohol while you are taking Tecfidera, because it may increase the risk of side effects such as inflammation of the stomach (gastritis), especially in those with a history of stomach problems. You should avoid drinking alcohol, especially strong spirits, for at least an hour after taking Tecfidera; however, one glass of alcohol, now and then at a different time of day to your Tecfidera dose is considered OK.

Be aware that alcohol can also exacerbate MS symptoms, such as imbalance, tremor, numbness, and lack of coordination, even after just one drink in some people. If alcohol affects you in this way, then it is probably better that you avoid alcohol completely. The risks of alcohol consumption for people with MS are still being studied.