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M-Phen Side Effects

Generic Name: codeine / phenylephrine / promethazine

Note: This page contains information about the side effects of codeine / phenylephrine / promethazine. Some of the dosage forms included on this document may not apply to the brand name M-Phen.

For the Consumer

Applies to codeine / phenylephrine / promethazine: oral elixir, oral syrup

In addition to its needed effects, some unwanted effects may be caused by codeine / phenylephrine / promethazine. In the event that any of these side effects do occur, they may require medical attention.

Major Side Effects

You should check with your doctor immediately if any of these side effects occur when taking codeine / phenylephrine / promethazine:

Incidence not known:
  • Abdominal or stomach pain
  • black, tarry stools
  • bleeding gums
  • bloating
  • blood in the urine or stools
  • blurred vision
  • chest pain
  • chills
  • clay-colored stools
  • cold sweats
  • confusion
  • constipation
  • convulsions
  • cough
  • dark urine
  • decrease in the frequency of urination
  • decrease in urine volume
  • difficult or troubled breathing
  • difficulty in passing urine (dribbling)
  • dizziness
  • dizziness, faintness, or lightheadedness when getting up from lying or sitting position
  • fainting
  • fast, pounding, or irregular heartbeat or pulse
  • fever
  • headache
  • high fever
  • increased sweating
  • irregular, fast or slow, or shallow breathing
  • lightheadedness
  • loss of appetite
  • loss of bladder control
  • nausea or vomiting
  • nervousness
  • painful or difficult urination
  • pale or blue lips, fingernails, or skin
  • pinpoint red spots on the skin
  • pounding in the ears
  • rash or itching
  • severe muscle stiffness
  • shakiness in the legs, arms, hands, or feet
  • slow or fast heartbeat
  • sore throat
  • sores, ulcers, or white spots on the lips or in the mouth
  • stomach pain
  • swollen glands
  • tiredness
  • trembling or shaking of the hands or feet
  • unpleasant breath odor
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • unusually pale skin
  • vomiting of blood
  • yellow eyes or skin

Minor Side Effects

Some of the side effects that can occur with codeine / phenylephrine / promethazine may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common:
  • Drowsiness
Incidence not known:
  • Anxiety
  • blurred or loss of vision
  • confusion
  • confusion about identity, place, and time
  • constipation
  • disturbed color perception
  • double vision
  • dry mouth
  • false or unusual sense of well-being
  • halos around lights
  • increased sensitivity of the skin to sunlight
  • night blindness
  • overbright appearance of lights
  • redness or other discoloration of the skin
  • relaxed and calm
  • restlessness
  • seeing, hearing, or feeling things that are not there
  • severe sunburn
  • sleepiness or unusual drowsiness
  • trouble sleeping
  • tunnel vision

For Healthcare Professionals

Applies to codeine / phenylephrine / promethazine: oral syrup

Nervous system

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 phenylephrine have included headache, dizziness, nervousness, restlessness, tremor, insomnia, convulsions, and central nervous system depression. Nervous system side effects of promethazine are common and include excessive sedation, drowsiness, fatigue, paradoxical excitation, and decreased motor coordination. Extrapyramidal effects (including oculogyric crises, torticollis and tongue protrusion), encephalitic symptoms, convulsions, and psychosis have been rarely reported.[Ref]

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 nonusers.[Ref]

Other

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. Other side effects of promethazine have rarely included the neuroleptic malignant syndrome.[Ref]

Fever, altered consciousness, autonomic dysfunction, and muscle rigidity are the hallmarks of the neuroleptic malignant syndrome. The neuroleptic malignant syndrome is associated with a case fatality rate of about 20%. Immediate discontinuation of promethazine and intensive monitoring and supportive care are indicated.[Ref]

Cardiovascular

Cardiovascular adverse effects of codeine have included hypotension and dizziness. Cardiovascular side effects of phenylephrine have included palpitations, arrhythmias, and cardiovascular collapse with hypotension. Cardiovascular effects of promethazine have included rarely observed tachycardia, bradycardia, and transient hypotension. Prolongation of the QT interval, heart block, and malignant arrhythmias have been reported in association with other phenothiazines.[Ref]

Gastrointestinal

Gastrointestinal side effects of codeine have included nausea, vomiting, and constipation. Severe constipation and ileus resulting in colonic perforation have been also reported. Four cases of acute pancreatitis have been reported. Gastrointestinal side effects of phenylephrine have included nausea. Gastrointestinal side effects of promethazine have included nausea and vomiting.[Ref]

Genitourinary

Genitourinary side effects of codeine have included urinary retention. Genitourinary side effects of phenylephrine have included dysuria.[Ref]

Dermatologic

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.[Ref]

Renal

Renal side effects of codeine have included acute renal failure (which may respond to naloxone therapy).[Ref]

Immunologic

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. Immunologic side effects of promethazine have included rare reports of a systemic lupus erythematosus syndrome.[Ref]

Hypersensitivity

Hypersensitivity reactions have included rare reports of rash, pruritus, hypotension, photosensitivity, and tachycardia.[Ref]

Hematologic

Hematologic effects of promethazine have included rare cases of neutropenia.[Ref]

Psychiatric

Psychiatric side effects of phenylephrine have included hallucinations, fear, and anxiety.[Ref]

Respiratory

Respiratory side effects of phenylephrine have included respiratory difficulty.[Ref]

General

General side effects of phenylephrine have included pallor and weakness.[Ref]

References

1. "Product Information. Phenergan with Codeine (codeine-promethazine)" Wyeth-Ayerst Laboratories, Philadelphia, PA.

2. "Multum Information Services, Inc. Expert Review Panel"

3. "Product Information. Ah-Chew D (phenylephrine)." WE Pharmaceuticals Inc, Ramona, CA.

4. "Product Information. Calcidrine (codeine)." Abbott Pharmaceutical, Abbott Park, IL.

5. Hastier P, Buckley MJM, Peten EP, Demuth N, Dumas R, Demarquay JF, CaroliBosc FX, Delmont JP "A new source of drug-induced acute pancreatitis: Codeine." Am J Gastroenterol 95 (2000): 3295-8

6. Gonzalogarijo MA, Revengaarranz F "Fixed drug eruption due to codeine." Br J Dermatol 135 (1996): 498-9

7. Hill SA, Quinn K, Shelly MP, Park GR "Reversible renal failure following opioid administration." Anaesthesia 46 (1991): 938-9

8. Lin RY, Barnard M "Skin testing with food, codeine, and histamine in exercise-induced anaphylaxis." Ann Allergy 70 (1993): 475-8

9. "Product Information. Phenergan (promethazine)." Wyeth-Ayerst Laboratories, Philadelphia, PA.

Not all side effects for M-Phen may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

More about M-Phen (codeine / phenylephrine / promethazine)

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Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.

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