phenylephrine sustained-release capsules
Generic Name: guaifenesin/phenylephrine (gwye-FEN-e-sin/fen-il-EF-rin)
Brand Name: Examples include Entex LA and Guaphenyl LA
Guaifenesin/phenylephrine sustained-release capsules is used for:
Relieving congestion, cough, and throat and airway irritation due to colds, flu, or hay fever. It may also be used for other conditions as determined by your doctor.
Guaifenesin/phenylephrine sustained-release capsules is a decongestant and expectorant combination. It works by constricting blood vessels and shrinking swollen and congested nasal tissues (mucous membranes) and by thinning and loosening mucus in the airway. This allows you to breathe more easily and makes coughs more productive.
Do NOT use guaifenesin/phenylephrine sustained-release capsules if:
- you are allergic to any ingredient in guaifenesin/phenylephrine sustained-release capsules
- you have severe high blood pressure, severe heart blood vessel disease, rapid heartbeat, or other severe heart problems
- you have taken furazolidone or a monoamine oxidase inhibitor (MAOI) (eg, phenelzine) within the last 14 days
Contact your doctor or health care provider right away if any of these apply to you.
Before using guaifenesin/phenylephrine sustained-release capsules:
Some medical conditions may interact with guaifenesin/phenylephrine sustained-release capsules. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have a fast, slow, or irregular heartbeat
- if you have a history of adrenal gland problems (eg, tumor), heart problems, high blood pressure, diabetes, heart blood vessel problems, stroke, glaucoma, an enlarged prostate, seizures, or an overactive thyroid
- if you have chronic cough
Some MEDICINES MAY INTERACT with guaifenesin/phenylephrine sustained-release capsules. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Beta-blockers (eg, propranolol), catechol-O-methyltransferase (COMT) inhibitors (eg, tolcapone), furazolidone, indomethacin, MAOIs (eg, phenelzine), or tricyclic antidepressants (eg, amitriptyline) because they may increase the risk of guaifenesin/phenylephrine sustained-release capsules's side effects
- Digoxin or droxidopa because the risk of irregular heartbeat or heart attack may be increased
- Bromocriptine because the risk of its side effects may be increased by guaifenesin/phenylephrine sustained-release capsules
- Guanadrel, guanethidine, mecamylamine, methyldopa, or reserpine because their effectiveness may be decreased by guaifenesin/phenylephrine sustained-release capsules
This may not be a complete list of all interactions that may occur. Ask your health care provider if guaifenesin/phenylephrine sustained-release capsules may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use guaifenesin/phenylephrine sustained-release capsules:
Use guaifenesin/phenylephrine sustained-release capsules as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Take guaifenesin/phenylephrine sustained-release capsules by mouth with or without food.
- Take guaifenesin/phenylephrine sustained-release capsules with a full glass of water (8 oz/240 mL) unless your doctor directs otherwise.
- Swallow guaifenesin/phenylephrine sustained-release capsules whole. Do not break, crush, or chew before swallowing.
- If you miss a dose of guaifenesin/phenylephrine sustained-release capsules, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.
Ask your health care provider any questions you may have about how to use guaifenesin/phenylephrine sustained-release capsules.
Important safety information:
- Guaifenesin/phenylephrine sustained-release capsules may cause dizziness. This effect may be worse if you take it with alcohol or certain medicines. Use guaifenesin/phenylephrine sustained-release capsules with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
- Do not take diet or appetite control medicines while you are taking guaifenesin/phenylephrine sustained-release capsules without checking with your doctor.
- Do NOT take more than the recommended dose or use for longer than prescribed without checking with your doctor.
- If your symptoms do not get better within 5 to 7 days or if they get worse, check with your doctor.
- Guaifenesin/phenylephrine sustained-release capsules may interfere with certain lab tests. Be sure your doctor and lab personnel know you are taking guaifenesin/phenylephrine sustained-release capsules.
- Tell your doctor or dentist that you take guaifenesin/phenylephrine sustained-release capsules before you receive any medical or dental care, emergency care, or surgery.
- Use guaifenesin/phenylephrine sustained-release capsules with caution in the ELDERLY; they may be more sensitive to its effects.
- Caution is advised when using guaifenesin/phenylephrine sustained-release capsules in CHILDREN; they may be more sensitive to its effects.
- PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using guaifenesin/phenylephrine sustained-release capsules while you are pregnant. It is not known if guaifenesin/phenylephrine sustained-release capsules is found in breast milk. Do not breast-feed while taking guaifenesin/phenylephrine sustained-release capsules.
Possible side effects of guaifenesin/phenylephrine sustained-release capsules:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Dizziness; excitability; headache; nausea; nervousness or anxiety; trouble sleeping; weakness.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); difficulty urinating; fast or irregular heartbeat; hallucinations; seizures; severe dizziness, lightheadedness, or headache; tremor.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include blurred vision; confusion; hallucinations; seizures; severe dizziness, lightheadedness, or headache; severe drowsiness; unusually fast, slow, or irregular heartbeat; vomiting.Proper storage of guaifenesin/phenylephrine sustained-release capsules:
Store guaifenesin/phenylephrine sustained-release capsules at room temperature, between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep guaifenesin/phenylephrine sustained-release capsules out of the reach of children and away from pets.
- If you have any questions about guaifenesin/phenylephrine sustained-release capsules, please talk with your doctor, pharmacist, or other health care provider.
- Guaifenesin/phenylephrine sustained-release capsules is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- Check with your pharmacist about how to dispose of unused medicine.
This information should not be used to decide whether or not to take guaifenesin/phenylephrine sustained-release capsules or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about guaifenesin/phenylephrine sustained-release capsules. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to guaifenesin/phenylephrine sustained-release capsules. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using guaifenesin/phenylephrine sustained-release capsules.
Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.