Colistin and neomycin are antibiotics that fight bacteria.

Hydrocortisone is a steroid. It reduces the actions of chemicals in the body that cause inflammation.

Thonzonium is a wetting agent.

Colistin, hydrocortisone, neomycin, and thonzonium otic (for the ears) is a combination medicine used to treat outer ear infections caused by bacteria.

colistin, hydrocortisone, neomycin, and thonzonium will not treat a viral infection such as herpes or shingles.

Colistin, hydrocortisone, neomycin, and thonzonium otic may also be used for purposes not listed in this medication guide.

You should not use colistin, hydrocortisone, neomycin, and thonzonium if you have a hole in your ear drum (ruptured ear drum).

Follow all directions on your prescription label. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Before using the medicine, clean and dry your ear canal with sterile cotton.

Shake the ear drops well just before each use.

To use the ear drops:

• Lie down or tilt your head with your ear facing upward. Open the ear canal by gently pulling your ear back, or pulling downward on the earlobe when giving this medicine to a child.

• Hold the dropper upside down over your ear and drop the correct number of drops into the ear.

• Stay lying down or with your head tilted for at least 5 minutes. You may use a small piece of cotton to plug the ear and keep the medicine from draining out.

• Do not touch the dropper tip or place it directly in your ear. It may become contaminated. Wipe the tip with a clean tissue but do not wash with water or soap.

As an alternative to dropping the medicine into your ear, you may insert a small piece of cotton into the ear canal and then drop the medicine directly onto the cotton to soak it. Leave the cotton in your ear for at least 24 hours, and keep it moist by adding a few drops of the medicine to the cotton every 4 hours. Replace the cotton at least every 24 hours. Follow your doctor's instructions about the use of cotton with this medication.

Call your doctor if your symptoms do not improve, or if they get worse while using colistin, hydrocortisone, neomycin, and thonzonium otic.

Use this medicine for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Skipping doses may also increase your risk of further infection that is resistant to antibiotics.

Do not use colistin, hydrocortisone, neomycin, and thonzonium otic for longer than 10 days in a row unless your doctor tells you to. Long-term use of neomycin may cause damage to your hearing.

Store at room temperature away from moisture and heat.

You should not use this medicine if you are allergic to colistin, hydrocortisone, neomycin, or thonzonium, or if you have a hole in your ear drum (ruptured ear drum).

FDA pregnancy category C. It is not known whether colistin, hydrocortisone, neomycin, and thonzonium otic will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medicine.

Colistin, hydrocortisone, neomycin, and thonzonium otic can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

This medicine should not be used on a child younger than 1 year old.

Use the missed dose as soon as you remember. If it is almost time for your next dose, wait until then to use the medicine and skip the missed dose. Do not use extra medicine to make up the missed dose.

An overdose of colistin, hydrocortisone, neomycin, and thonzonium is not expected to be dangerous. Seek emergency medical attention or call the Poison Help line at 1-800-222-1222 if anyone has accidentally swallowed the medication.

This medicine is for use only in the ears. Avoid getting the medicine in your eyes, mouth, and nose, or on your skin. Rinse with water if this medicine gets in or on these areas.

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

This medicine may cause serious side effects. Stop using this medicine and call your doctor at once if you have:

• severe burning or other irritation after using the ear drops;

• hearing loss; or

• skin rash, redness, swelling, itching, dryness, or scaling.

Common side effects of colistin, hydrocortisone, neomycin, and thonzonium may include:

• mild itching after using the ear drops.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

It is not likely that other drugs you take orally or inject will have an effect on colistin, hydrocortisone, neomycin, and thonzonium otic used in the ears. But many drugs can interact with each other. Tell each of your healthcare providers about all medicines you use, including prescription and over-the-counter medicines, vitamins, and herbal products.