Guaifenesin/Theophylline, Oral

What are other names for this medicine?

Type of medicine: bronchodilator; expectorant

Generic and brand names: guaifenesin and theophylline, oral; Elixophyllin-GG; Quibron

What is this medicine used for?

This medicine is taken to treat the symptoms of lung problems such as asthma, emphysema, and bronchitis. Guaifenesin is an expectorant used to help bring up mucus from the lungs, to thin secretions, and to make a cough productive. Theophylline is a bronchodilator that opens up the air passages (bronchial tubes) in the lungs.

What should my healthcare provider know before I take this medicine?

Before taking this medicine, tell your healthcare provider if you have ever had:

• an allergic reaction to any medicine
• an irregular heart beat (arrhythmia)
• heart failure or other heart disease
• high blood pressure
• liver disease
• problems with alcohol abuse
• seizures
• thyroid disease
• ulcers.

Tell your healthcare provider if you smoke.

Females of childbearing age: Tell your healthcare provider if you are pregnant or plan to become pregnant. It is not known whether this medicine will harm an unborn baby. Do not breast-feed while taking this medicine without your healthcare provider's approval.

How do I take it?

Take this medicine exactly as your healthcare provider prescribes. Do not take more or less or take it longer than prescribed. Do not stop taking this medicine without your healthcare provider's approval.

Take your doses at the same time every day to keep a constant level medicine in your blood. Take it 1 hour before or 2 hours after meals.

This medicine may come in different forms. If you have extended-release tablets, do not break, crush, or chew them. Swallow them whole. Ask your pharmacist if you have the extended-release tablets.

Drink plenty of water with this medicine to help loosen the mucus or phlegm in the lungs.

If you miss a dose, take it as soon as you remember unless it is almost time for the next dose. In that case, skip the missed dose and take the next one as directed. Do not take double doses. If you are not sure of what to do if you miss a dose, or if you miss more than one dose, contact your healthcare provider.

What should I watch out for?

Do not give a child under age 2 any cough and cold medicines unless specifically instructed to do so by your healthcare provider.

This medicine may increase the stimulant effects of caffeine. Avoid foods and drinks containing caffeine (for example, coffee, tea, cocoa, colas, and chocolate).

You may need to have blood tests regularly to see how this medicine affects you. Keep all appointments for these tests.

This medicine may cause dizziness. Use caution when driving or operating machinery.

Certain types of diets (such as high-protein, low-carbohydrate, or high-fat diets) may affect how this medicine works. Discuss this with your healthcare provider.

Inform your healthcare provider if you start or stop smoking. This may affect the way the medicine works in your body.

What are the possible side effects?

Along with its needed effects, your medicine may cause some unwanted side effects. Some effects may be very serious. Some side effects may go away as your body adjusts to the medicine. Tell your healthcare provider if you have any side effects that continue or get worse.

Serious (report these to your healthcare provider right away): Diarrhea, nausea, vomiting, abdominal pain, irregular or rapid (pounding) heartbeat, seizures, muscle twitching, rapid breathing, headache that does not go away.

Other: Increased urination, dizziness, headache, rash, nervousness, trouble sleeping.

What products might interact with this medicine?

When you take this medicine with other medicines, it can change the way this or any of the other medicines work. Nonprescription medicines, vitamins, natural remedies, and certain foods may also interact. Using these products together might cause harmful side effects. Talk to your healthcare provider if you are taking:

• aminoglutethimide (Cytadren)
• antibiotics such as erythromycin (Ery-Tabs, E.E.S., Eryc), clarithromycin (Biaxin), doxycycline (Vibramycin), ciprofloxacin (Cipro), nafcillin (Nafcil), rifabutin (Mycobutin), rifampin (Rifadin, Rimactane), and isoniazid (Nydrazid)
• antifungals such as ketoconazole (Nizoral), fluconazole (Diflucan), and itraconazole (Sporanox)
• antiseizure medicines such as carbamazepine (Tegretol, Carbatrol, Epitol), phenobarbital, and phenytoin (Dilantin)
• barbiturates such as butabarbital (Butisol), and pentobarbital (Nembutal)
• charcoal
• cimetidine (Tagamet)
• disulfiram (Antabuse)
• ephedrine, pseudoephedrine (Sudafed, and other cold medicines containing pseudoephedrine)
• fluvoxamine (Luvox)
• foods and drinks containing caffeine (coffee, tea, cocoa, colas, and chocolate)
• herbal remedies such as St. John's wort, valerian, kava, gotu kola, green tea, guarana, ephedra, and yohimbe
• nevirapine (Viramune)
• propranolol (Inderal, Inderal LA)
• quinidine
• zileuton (Zyflo).

Do not smoke cigarettes while taking this medicine. Do not drink alcohol while taking this medicine without your healthcare provider's approval.

Keep a list of all your medicines (prescription, nonprescription, supplements, natural remedies, and vitamins) with you. Be sure that you tell all healthcare providers who treat you about all the products you are taking.

How should I store this medicine?

Store this medicine at room temperature. Keep the container tightly closed. Protect it from heat, high humidity, and bright light.

This advisory includes selected information only and may not include all side effects of this medicine or interactions with other medicines. Ask your healthcare provider or pharmacist for more information or if you have any questions.

Ask your pharmacist for the best way to dispose of outdated medicine or medicine you have not used. Do not throw medicine in the trash.

Keep all medicines out of the reach of children.

Do not share medicines with other people.