Gentex LQ Side Effects
Generic name: carbetapentane / guaifenesin / phenylephrine
Medically reviewed by Drugs.com. Last updated on Apr 17, 2022.
Note: This document contains side effect information about carbetapentane / guaifenesin / phenylephrine. Some dosage forms listed on this page may not apply to the brand name Gentex LQ.
Applies to carbetapentane/guaifenesin/phenylephrine: oral liquid, oral syrup, oral tablet, oral tablet extended release.
Warning
Do not give this medication to a child younger than 4 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.
Do not use a cough or cold medicine if you have taken an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine.
Get emergency medical help if you have any of these signs of an allergic reaction while taking carbetapentane/guaifenesin/phenylephrine: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Stop using this medicine and call your doctor at once if you have:
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fast or pounding heartbeats;
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confusion, hallucinations, unusual thoughts or behavior;
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severe dizziness, anxiety, restless feeling, or nervousness;
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little or no urinating;
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easy bruising or bleeding, unusual weakness, fever, chills, body aches, flu symptoms; or
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dangerously high blood pressure (severe headache, blurred vision, buzzing in your ears, anxiety, chest pain, shortness of breath, uneven heartbeats, seizure).
Common side effects may include:
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dizziness, drowsiness, headache, weakness;
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dry mouth, nose, or throat, increased sweating or urination;
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nausea, mild stomach pain;
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sleep problems (insomnia); or
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feeling restless or excited (especially in children).
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.
For Healthcare Professionals
Applies to carbetapentane/guaifenesin/phenylephrine: oral liquid, oral syrup, oral tablet, oral tablet extended release.
Nervous system
Nervous system side effects have included nervousness, lightheadedness, excitability, restlessness, dizziness, tenseness, convulsions, CNS depression, and insomnia.[Ref]
Cardiovascular
Cardiovascular side effects have included arrhythmias and hypotension with cardiovascular collapse.[Ref]
Gastrointestinal
Gastrointestinal side effects have included nausea and vomiting.[Ref]
Psychiatric
Psychiatric side effects have included fear, anxiety, and hallucinations.[Ref]
Respiratory
Respiratory side effects have included respiratory difficulty.[Ref]
Genitourinary
Genitourinary side effects have included dysuria.[Ref]
General
General side effects have included weakness and pallor.[Ref]
More about Gentex LQ (carbetapentane / guaifenesin / phenylephrine)
- Check interactions
- Compare alternatives
- Side effects
- Dosage information
- During pregnancy
- Drug class: upper respiratory combinations
Related treatment guides
References
1. Product Information. Phencarb GG (carbetapentane / guaifenesin / phenylephrine). Boca Pharmacal Inc. 2004.
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Some side effects may not be reported. You may report them to the FDA.
