Chlorpheniramine is an antihistamine. It blocks the effects of the naturally occurring chemical histamine in the body and reduces congestion.

Dihydrocodeine is a narcotic. It is a pain reliever and a cough suppressant.

Phenylephrine is a decongestant. It works by constricting (shrinking) blood vessels (veins and arteries) in the body. Constriction of blood vessels in the sinuses and nose decreases congestion.

Chlorpheniramine, dihydrocodeine, and phenylephrine is used to treat cough and nasal congestion associated with upper respiratory tract infections and allergies.

Chlorpheniramine, dihydrocodeine, and phenylephrine may also be used for purposes other than those listed in this medication guide.

Use caution when driving, operating machinery, or performing other hazardous activities. Chlorpheniramine, dihydrocodeine, and phenylephrine may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while taking chlorpheniramine, dihydrocodeine, and phenylephrine.

Chlorpheniramine, dihydrocodeine, and phenylephrine may increase the effects of other drugs that cause drowsiness, including antidepressants, alcohol, antihistamines, sedatives (used to treat insomnia), pain relievers, anxiety medicines, seizure medicines, and muscle relaxants. Tell your doctor about all medicines that you are taking, and do not take any other medicine without first talking to your doctor.

Dihydrocodeine is habit forming. It is possible become physically and/or psychologically dependent on the medication. Do not take more than the prescribed amount of medication or take it for longer than is directed by your doctor. Withdrawal effects may occur if chlorpheniramine, dihydrocodeine, and phenylephrine is stopped suddenly after several weeks of continuous use. Your doctor may recommend a gradual reduction in dose.

Do not take chlorpheniramine, dihydrocodeine, and phenylephrine if you have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) in the last 14 days. A dangerous drug interaction could occur, leading to serious side effects.

Before taking chlorpheniramine, dihydrocodeine, and phenylephrine, tell your doctor if you have

• epilepsy or another seizure disorder;

• been diagnosed with sleep apnea (periods of not breathing during sleep);

• thyroid problems;

• asthma;

• gallbladder disease;

• a head injury;

• Addison's disease;

• diabetes;

• glaucoma;

• an ulcer or an obstruction in the stomach;

• bladder problems or difficulty urinating;

• an enlarged prostate;

• high blood pressure, irregular heartbeats, or any type of heart disease;

• kidney problems; or

• liver problems.

You may not be able to take chlorpheniramine, dihydrocodeine, and phenylephrine, or you may require a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above.

Chlorpheniramine, dihydrocodeine, and phenylephrine is in the FDA pregnancy category C. This means that it is not known whether chlorpheniramine, dihydrocodeine, and phenylephrine will be harmful to an unborn baby. Do not take chlorpheniramine, dihydrocodeine, and phenylephrine without first talking to your doctor if you are pregnant or could become pregnant during treatment.

It is not known whether chlorpheniramine, dihydrocodeine, and phenylephrine passes into breast milk. Do not take chlorpheniramine, dihydrocodeine, and phenylephrine without first talking to your doctor if you are breast-feeding a baby.

If you are over 60 years of age, you may be more likely to experience side effects from chlorpheniramine, dihydrocodeine, and phenylephrine. Your doctor may prescribe a lower dose of this medication.

The safety of chlorpheniramine, dihydrocodeine, and phenylephrine for children younger than 2 years of age has not been established.