Phenylhistine Expectorant Side Effects
Generic name: codeine / guaifenesin / pseudoephedrine
Medically reviewed by Drugs.com. Last updated on Jul 13, 2022.
Note: This document contains side effect information about codeine / guaifenesin / pseudoephedrine. Some of the dosage forms listed on this page may not apply to the brand name Phenylhistine Expectorant.
For the Consumer
WarningFor all patients taking this drug:
- This drug has an opioid drug in it. Opioid drugs can put you at risk for addiction, abuse, and misuse. Misuse or abuse of this drug can lead to overdose and death. If you have questions, talk with your doctor.
- This drug has an opioid drug in it. Severe side effects have happened when opioid drugs were used with benzodiazepines or other drugs that may make you drowsy or slow your actions. This includes slow or troubled breathing and death. Benzodiazepines include drugs like alprazolam, diazepam, and lorazepam. Benzodiazepines may be used to treat many health problems like anxiety, trouble sleeping, or seizures. If you have questions, talk with your doctor.
- Many drugs interact with this drug and can raise the chance of side effects like deadly breathing problems. Talk with your doctor and pharmacist to make sure it is safe to use this drug with all of your drugs.
- Do not take with alcohol or products that have alcohol. Unsafe and sometimes deadly effects may happen.
- Get medical help right away if you feel very sleepy, very dizzy, or if you pass out. Caregivers or others need to get medical help right away if the patient does not respond, does not answer or react like normal, or will not wake up.
- Very bad and sometimes deadly breathing problems have happened with this drug. Talk with the doctor.
- Get medical help right away if you have slow breathing, shallow breathing, or trouble breathing.
- This drug is not for use in children younger than 18 years of age. The benefits of taking this drug for a cough due to allergies, a cold, or other infection do not outweigh the risks in children. If your child has been given this drug or if you have any questions, talk with your child's doctor.
What are some side effects that I need to call my doctor about right away?
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Very bad dizziness or passing out.
- Chest pain or pressure or a fast heartbeat.
- Trouble breathing, slow breathing, or shallow breathing.
- Noisy breathing.
- Feeling very sleepy.
- Feeling confused.
- A heartbeat that does not feel normal.
- Hallucinations (seeing or hearing things that are not there).
- Mood changes.
- Very bad belly pain.
- Very bad constipation.
- Very bad headache.
- Trouble passing urine.
- Change in eyesight.
- Feeling very tired or weak.
What are some other side effects of this drug?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Feeling nervous and excitable.
- Trouble sleeping.
- Feeling sleepy.
- Upset stomach or throwing up.
- Sweating a lot.
- Feeling tired or weak.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.
For Healthcare Professionals
Frequency not reported: CNS depression, lightheadedness, dizziness, sedation, headache, convulsions, weakness
Frequency not reported: Restlessness, dizziness, weakness, headache, drowsiness, tremor[Ref]
Hypotension is rare and has been reported most frequently with high doses of codeine.
Pseudoephedrine causes vasoconstriction which generally does not produce hypertension, but may be problematic for patients with preexisting hypertension. Arrhythmias may be produced in predisposed patients. Rarely, pseudoephedrine has been reported to cause coronary artery spasm and chest pain.[Ref]
Frequency not reported: Nausea, vomiting, constipation, biliary tract spasm, increased colonic motility, toxic dilation
Frequency not reported: Oliguria, urinary retention, antidiuretic effect
Frequency not reported: Urinary retention[Ref]
Frequency not reported: Hypersensitivity reactions (pruritus, urticaria)
Frequency not reported: Fixed drug eruptions[Ref]
Frequency not reported: Rash
Frequency not reported: Rash
Frequency not reported: Fixed drug eruption in the form of erythematous nodular patches, rash[Ref]
Frequency not reported: Visual disturbances
Frequency not reported: Angle-closure glaucoma
Frequency not reported: Euphoria, dysphoria, transient hallucination, disorientation
Frequency not reported: Hallucinations (particularly in children), anxiety, excitability, insomnia
Frequency not reported: Respiratory depression
Respiratory depression has been associated with antitussive use of codeine in young children. Respiratory depression and death have occurred in children who received codeine in the postoperative period following tonsillectomy and/or adenoidectomy. Further investigation has shown these patients to be ultra-rapid metabolizers of codeine. Children with obstructive sleep apnea who are treated with codeine appear to be particularly sensitive to the respiratory depressant effects of codeine.
More about Phenylhistine Expectorant (codeine / guaifenesin / pseudoephedrine)
Related treatment guides
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11. Camisa C "Fixed drug eruption due to pseudoephedrine." Cutis 41 (1988): 339-40
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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.