You've snagged yourself a sinus infection or are battling a bout of strep throat... complete with that daggers-puncturing-your-tonsils feeling. Of course, it comes at the worst time ever (because, when doesn’t it?) and you’re also prepping for your best friend’s wedding/a holiday party/some fancy get-together where alcohol will be present. You’ve heard it before: Consuming alcohol while taking antibiotics is bad. But one little sip (or 12) really won’t be a life-ruiner, right?

Not so fast with the champagne there, friend. First, it's important to remember why you’re on antibiotics to begin with: You feel awful and, with some help from your prescription, your body is working to fight off a nasty bacterial infection. (Antibiotics cannot treat anything viral, like a flu.) Basically, antibiotics kill the bacteria that can give you a sore throat, make your ear ache, and spike your temperatures. (Kick-start your new, healthy routine with Women's Health's 12-Week Total-Body Transformation!)

And, while drinking alcohol won’t reduce how effectively antibiotics make that happen, it can worsen many of the side effects—such as mild stomach discomfort, diarrhea, nausea, and drowsiness—that are associated with antibiotics, says Louise M. Dembry, M.D., professor of medicine, infectious diseases, and epidemiology at the Yale University School of Medicine and School of Public Health. And it's not exactly ideal if you’re out at a function and a slap of exhaustion (or diarrhea!) hits you in the face. Meanwhile, alcohol can also slow your body's ability to "bounce back" and restore its energy levels once that infection is no more.