Similar medicines derived from the guaiac tree were in use as a generic remedy by Native Americans when explorers reached North America in the 1500s, but guaifenesin was first approved by the Food and Drug Administration (FDA) in 1952.
Drink plenty of extra fluids while you are taking this medication. Extra fluids may help to relieve chest congestion. Do not crush or chew the tablets. Swallow them whole or break them in half where they are scored to make them easier to swallow.
Talk to your doctor before taking guaifenesin if you have other medical conditions or if you take other medicines.
Guaifenesin is in the FDA pregnancy category C. This means that it is not known whether guaifenesin will harm an unborn baby. Do not take this medication without first talking to your doctor if you are pregnant.
It is also not known whether guaifenesin passes into breast milk. Do not take this medication without first talking to your doctor if you are breast-feeding a baby.
Guaifenesin has not been approved by the FDA for use by children younger than 2 years of age.
Take guaifenesin exactly as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.
Take each dose with a full glass of water. Drink plenty of extra fluids while you are taking this medication. Extra fluids may help to relieve chest congestion.
Take guaifenesin with food if it upsets your stomach.
Do not crush or chew the tablets. Swallow them whole or break them in half where they are scored to make them easier to swallow.
The capsules may be swallowed whole, or they may be opened and the contents sprinkled on soft food such as pudding or applesauce then swallowed whole without crushing or chewing.
To ensure that you get a correct dose, measure the liquid form of guaifenesin with a special dose-measuring spoon or cup, not with a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist where you can get one.
Store guaifenesin at room temperature away from moisture, heat, and direct sunlight.
Guaifenesin comes as a tablet, a capsule, an extended-release (long-acting) tablet, dissolving granules, and a syrup (liquid) to take by mouth. The tablets, capsules, dissolving granules, and syrup are usually taken with or without food every 4 hours as needed. The extended-release tablet is usually taken with or without food every 12 hours. Follow the directions on the package or on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take guaifenesin exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Guaifenesin comes alone and in combination with antihistamines, cough suppressants, and decongestants. Ask your doctor or pharmacist for advice on which product is best for your symptoms. Check nonprescription cough and cold product labels carefully before using two or more products at the same time. These products may contain the same active ingredient(s) and taking them together could cause you to receive an overdose. This is especially important if you will be giving cough and cold medications to a child.
Nonprescription cough and cold combination products, including products that contain guaifenesin, can cause serious side effects or death in young children. Do not give these products to children younger than 4 years of age. If you give these products to children 4 to 11 years of age, use caution and follow the package directions carefully.
If you are giving guaifenesin or a combination product that contains guaifenesin to a child, read the package label carefully to be sure that it is the right product for a child of that age. Do not give guaifenesin products that are made for adults to children.
Before you give a guaifenesin product to a child, check the package label to find out how much medication the child should receive. Give the dose that matches the child’s age on the chart. Ask the child’s doctor if you don’t know how much medication to give the child.
If you are taking the liquid, do not use a household spoon to measure your dose. Use the measuring spoon or cup that came with the medication or use a spoon made especially for measuring medication.
Swallow the extended-release tablets whole with a full glass of water. Do not break, crush, or chew them.
If you are taking the dissolving granules, empty the entire contents of the packet onto your tongue and swallow.
If your symptoms do not improve within 7 days or if you also have a high fever, a rash, or a headache that does not go away, call your doctor.