Phenhist Expectorant Side Effects
Generic Name: codeine / guaifenesin / pseudoephedrine
Note: This page contains side effects data for the generic drug codeine / guaifenesin / pseudoephedrine. It is possible that some of the dosage forms included below may not apply to the brand name Phenhist Expectorant.
It is possible that some side effects of Phenhist Expectorant may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.
For the Consumer
Applies to codeine / guaifenesin / pseudoephedrine: liquid, solution, suspension, syrup, tablets
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 while taking codeine / guaifenesin / pseudoephedrine:
Constipation; dizziness; drowsiness; excitability; headache; nausea; nervousness or anxiety; trouble sleeping; vomiting; weakness.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); blurred vision or other vision changes; confusion; difficulty urinating; fainting; fast, slow, or irregular heartbeat; hallucinations; mental or mood changes; persistent trouble sleeping; seizures; severe dizziness, lightheadedness, or headache; severe drowsiness; shallow breathing; tremor; uncontrolled muscle movement.
For Healthcare Professionals
Applies to codeine / guaifenesin / pseudoephedrine: oral liquid, oral tablet
Guaifenesin is generally well tolerated.
Opioids may result in psychotic symptoms in some patients.
One retrospective study of elderly patients who sustained a hip fracture suggested that the relative risk of hip fracture was 1.6 in patients using codeine compared to age-matched non-users.
Nervous system side effects of codeine have included mental and respiratory depression, stupor, delirium, somnolence, and dysphoria. An increased risk of falls and hip fractures has been associated with codeine therapy, particularly in the elderly. Nervous system side effects of guaifenesin have included dizziness and headache. Nervous system side effects of pseudoephedrine have included insomnia in up to 30% of patients. Tremor, anxiety, nervousness, and headache have also been reported.
Other side effects of codeine have included withdrawal symptoms after either abrupt cessation or fast tapering of narcotic analgesics, including codeine, and have included agitation, restlessness, anxiety, insomnia, tremor, abdominal cramps, blurred vision, vomiting and sweating.
Cardiovascular adverse effects of codeine have included hypotension and dizziness. Cardiovascular side effects of pseudoephedrine have included tachycardia. Some patients have developed hypertension and/or arrhythmias.
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.
One report evaluated the effect with 60 mg of pseudoephedrine on individuals in a hyperbaric chamber at 1 atmosphere (simulated scuba dive to 66 feet of sea water). Pseudoephedrine and depth (stimulated) were found to have significant but opposite effects on heart rate, although these effects were unlikely to be clinically significant during diving.
Gastrointestinal side effects of codeine have included nausea, vomiting, and constipation. Severe constipation and ileus resulting in colonic perforation have also been reported. Four cases of acute pancreatitis have been reported. Gastrointestinal side effects of guaifenesin have included upset stomach and vomiting with higher than recommended doses. Doses recommended for expectoration are rarely associated with gastrointestinal upset. Gastrointestinal side effects of pseudoephedrine have included anorexia and gastric irritation in approximately 5% of patients. Dry mouth, nose, or throat have occurred in up to 15% of patients.
Genitourinary side effects of codeine have included urinary retention.
Hypersensitivity side effects of pseudoephedrine have included fixed drug eruptions.
Dermatologic side effects of codeine have included rash. Codeine-induced rash may be related to direct stimulation of histamine release. There are also case reports of severe scarlatiniform eruptions. Dermatologic side effects of guaifenesin have also included rash.
Renal side effects of codeine have included acute renal failure (which may respond to naloxone therapy).
Immunologic side effects of codeine have included one study of a patient with exercise-induced anaphylaxis and three control subjects. This study found a correlation between codeine wheal size and recent exercise.
More about Phenhist Expectorant (codeine / guaifenesin / pseudoephedrine)
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