5 Medicine Bottle Warnings You Shouldn't Ignore

Sure, your pill bottle label says to avoid alcohol, but come on, who hasn't had a glass of wine while taking antibiotics? News flash: Blowing off these warnings and instructions can put your health at serious risk. Here are some of the most important directions to follow—and why.

ALCOHOL

  • Why it matters: Throwing back a few while using the pain reliever acetaminophen (also found in many cough, cold and flu medications) can put extra strain on your liver and could lead to lasting damage or, at worst, organ failure. Drinking while on antibiotics might cause nausea, and if you're already on a drug that makes you woozy, such as Xanax or Valium, you might feel even dizzier with alcohol.

SUNLIGHT

  • Why it matters: If you're on certain antibiotics or diabetes pills, just 10 unprotected minutes outdoors could cause burns.

Plus: 8 Foods to Eat to Beat Diabetes (And 5 to Avoid) »

DOSAGE

  • Why it matters: Even a basic—like acetaminophen, which is generally very safe—can be harmful if you take a little more than you should.

FOOD

  • Why it matters: Drugs such as ibuprofen and naproxen might irritate the stomach lining unless taken with food, which acts as a sort of protective cushion. And some pills require a little fat from food to be effectively absorbed into the bloodstream. On the other hand, a number of antibiotics aren't as potent as they need to be if your stomach is full.

GRAPEFRUIT

  • Why it matters: A compound in this fruit affects how your body processes many meds, so you can end up with too little or too much in your blood.

Plus: Is It Safe to Eat? How Long Expired Food Really Lasts »

Sources: William D. Chey, MD, professor and director of the GI Physiology Lab at the University of Michigan; Sandra Adamson Fryhofer, MD, adjunct associate professor at the Emory University School of Medicine in Atlanta; Joe Graedon, pharmacologist and co-founder of peoplespharmacy.com; John Whyte, MD, director of professional affairs and stakeholder engagement at the FDA Center for Drug Evaluation and Research.