Theophylline and Guaifenesin (Systemic)

Brand Names : Bronchial, Broncomar GG, Ed-Bron G, Elixophyllin-GG, Equibron G, Glyceryl-T, Quibron, Quibron-300, Slo-Phyllin GG, Theolate, Theocon, theophylline and glyceryl guaiacolate

Before Using This Medicine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For theophylline and guaifenesin combination medicine, the following should be considered:

Allergies - Tell your doctor if you have ever had any unusual or allergic reaction to aminophylline, guaifenesin, oxtriphylline, or theophylline.

Diet - Make certain your health care professional knows if you are on any special diet, such as a high-protein, low-carbohydrate or low-protein, high-carbohydrate diet.

Pregnancy - Theophylline is used to treat asthma in pregnant women. Although there are no studies on birth defects in humans, problems have not been reported. However, some studies in animals have shown that theophylline can cause birth defects when given in doses many times the human dose.

Because your ability to clear theophylline from your body may decrease later in pregnancy, your doctor may want to take blood samples during your pregnancy to measure the amount of medicine in the blood. This will help your doctor decide whether the dose of this medicine should be changed.

Theophylline crosses the placenta. Use of this medicine during pregnancy may cause unwanted effects, such as fast heartbeat, irritability, jitteriness, or vomiting, in the newborn infant if the amount of medicine in your blood is too high.

Several groups of women taking guaifenesin during pregnancy have been studied. In one group, when guaifenesin was taken during the first 3 months of pregnancy, the babies had more inguinal hernias than expected. However, more birth defects than expected did not occur in the babies of other groups of women taking guaifenesin during pregnancy. Studies with guaifenesin have not been done in animals.

Breast-feeding - Theophylline passes into breast milk and may cause irritability in babies of mothers taking this medicine. Guaifenesin has not been reported to cause problems in nursing babies.

Children - The side effects of theophylline are more likely to occur in newborn infants, who are usually more sensitive to the effects of this medicine.

Although there is no specific information about the use of guaifenesin in children, it is not expected to cause different side effects or problems in children than it does in adults.

Older adults - Patients older than 60 years of age are likely to require a lower dose than younger adults. If the amount of theophylline is too high, side effects are more likely to occur. Your doctor may want to take blood samples to determine whether a dose change is needed.

Although there is no specific information about the use of guaifenesin in the elderly, it is not expected to cause different side effects or problems in older people than it does in younger adults.

Other medicines - Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking theophylline and guaifenesin combination medicine, it is especially important that your health care professional know if you are taking any of the following:

• Beta-adrenergic blocking agents including those used in the eyes (acebutolol [e.g., Sectral], atenolol [e.g., Tenormin], betaxolol [e.g., Betoptic, Kerlone], bisoprolol [e.g., Zebeta], carteolol [e.g., Cartrol], labetalol [e.g., Normodyne], levobunolol [e.g., Betagan], metipranolol [e.g., OptiPranolol], metoprolol [e.g., Lopressor], nadolol [e.g., Corgard], oxprenolol [e.g., Trasicor], penbutolol [e.g., Levatol], pindolol [e.g., Visken], propranolol [e.g., Inderal], sotalol [e.g., Sotacor], timolol [e.g., Blocadren, Timoptic]) - These medicines may prevent theophylline from working properly

• Cimetidine (e.g., Tagamet) or
• Ciprofloxacin (e.g., Cipro) or
• Clarithromycin (e.g., Biaxin) or
• Enoxacin (e.g., Penetrex) or
• Erythromycin (e.g., E-Mycin) or
• Fluvoxamine (e.g., Luvox) or
• Mexiletine (e.g., Mexitil) or
• Pentoxifylline (e.g., Trental) or
• Tacrine (e.g., Cognex) or
• Thiabendazole or
• Ticlopidine (e.g., Ticlid) or
• Troleandomycin (e.g., TAO) - These medicines may increase the effects of theophylline

• Moricizine (e.g., Ethmozine) or
• Phenytoin (e.g., Dilantin) or
• Rifampin (e.g., Rifadin) - These medicines may decrease the effects of theophylline

• Smoking tobacco or marijuana - Starting or stopping smoking may change the effectiveness of this medicine

Other medical problems - The presence of other medical problems may affect the use of theophylline and guaifenesin combination medicine. Make sure you tell your doctor if you have any other medical problems, especially:

• Convulsions (seizures) - Theophylline may make this condition worse

• Heart failure or
• Liver disease or
• Underactive thyroid - The effects of theophylline may be increased