context: Is a hacking cough making you feel lousy? Don't grab a random box of cough medicine off the pharmacy shelf. Just a few basics will guide you to an over-the-counter ( OTC) medicine for the kind of cough you have. The role of cough medicine is to ease symptoms while your body heals. As a glance at the drugstore shelves will show you, there are many, many brands of OTC cough medicines. But there are only three basic types: Expectorants help thin mucus, making it easier to cough up. The ingredient guaifenesin is the only expectorant in the U. S., so look for it on the label if you need an expectorant. Suppressants help cut the number of times you cough. The active ingredient listed is usually dextromethorphan ( DM). Other cough suppressants include camphor, eucalyptus oil, and menthol. Combination cough products have more than one active ingredient. They have both guaifenesin and dextromethorphan. Cough medicines may also contain ingredients to help coat and soothe the throat. Combination products may have medicines to ease other symptoms, that may include decongestants for stuffy nose, antihistamines for allergies or a runny nose, or painkillers. Choose a medicine that matches your symptoms. Cough drops can also help relieve a cough and may ease a sore throat. Look at the ingredients. Don't just grab a bottle of anything that says "cough" on it. Check the label. Is it a suppressant or an expectorant? Is it both? Make sure you're getting what you need. Don't use medicine for more than 7 days. If you do, you could be covering up a more serious problem. See your doctor if your cough is severe or if it doesn't get better after a week. Always measure the correct dose. Some people can get too casual about taking OTC cough medicine, slugging it right out of the bottle at times. That's not smart, because even safe medicines in high doses can be very dangerous. High doses of cough medicine can cause serious problems, including brain damage, seizure, or death. Be careful with combination medicines. Many OTC cough medicines have multiple ingredients -- expectorants and suppressants along with decongestants, antihistamines, or painkillers. Select products with only the medicines that treat your symptoms. If your symptom is only a cough, for instance, you don't need a decongestant or painkiller. If you need to treat multiple symptoms, check other medicines you take to see if they contain the same ingredients. Don't take two medicines that have the same ingredients. If you have any questions, ask your pharmacist or doctor. Keep away from young children. Make sure to choose the right medicine based on your child's age. Don't give cough and cold medicine to children under age 4. For kids 4 to 6, ask your doctor first. And always make sure to follow the dosing directions on the label. Consider doing nothing. Waiting out a cough is the simplest option. Remember that most coughs don't need treatment. You don't have to take any medicine. Give your body a week and your cough will probably go away on its own. If it doesn't, see your doctor. Read the label. After you choose the right medicine for you, read the label carefully, so you understand how to take it, common side effects, and any warnings you need to be aware of.