Mepergan Fortis Side Effects
Generic Name: meperidine / promethazine
Note: This document contains side effect information about meperidine / promethazine. Some of the dosage forms listed on this page may not apply to the brand name Mepergan Fortis.
For the Consumer
Applies to meperidine / promethazine: oral capsule
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.
- Fast or slow heartbeat.
- A heartbeat that does not feel normal.
- Fever or chills.
- Sore throat.
- Hallucinations (seeing or hearing things that are not there).
- Mood changes.
- Feeling confused.
- Very hard stools (constipation).
- Feeling very sleepy.
- Chest pain.
- Trouble breathing, slow breathing, or shallow breathing.
- Any unexplained bruising or bleeding.
- Change in eyesight.
- Yellow skin or eyes.
- A very bad and sometimes deadly health problem called neuroleptic malignant syndrome (NMS) may happen. Call your doctor right away if you have any fever, muscle cramps or stiffness, dizziness, very bad headache, confusion, change in thinking, fast heartbeat, heartbeat that does not feel normal, or are sweating a lot.
- Some people who take this drug may have muscle movements that cannot be controlled. Call your doctor right away if you have any trouble controlling body movements or if you have muscle problems with your tongue, face, mouth, or jaw like tongue sticking out, puffing cheeks, mouth puckering, or chewing.
- A very bad and sometimes deadly health problem called serotonin syndrome may happen if you take this drug with drugs for depression, migraines, or certain other drugs. Call your doctor right away if you have agitation; change in balance; confusion; hallucinations; fever; fast or abnormal heartbeat; flushing; muscle twitching or stiffness; seizures; shivering or shaking; sweating a lot; very bad diarrhea, upset stomach, or throwing up; or very bad headache.
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:
- Upset stomach or throwing up.
- Hard stools (constipation).
- Feeling sleepy.
- Dry mouth.
- Sweating a lot.
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-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.
For Healthcare Professionals
The most frequently observed meperidine adverse reactions have included light-headedness, dizziness, sedation, nausea, vomiting, and sweating. Somnolence is the most prominent CNS effect reported with promethazine.[Ref]
Hyperexcitability and extrapyramidal movements have been reported following a single dose of promethazine.[Ref]
Common (1% to 10%): Lightheadedness, dizziness, sedation
Rare (less than 0.1%): Extrapyramidal reactions
Frequency not reported: Weakness, headache, tremor, uncoordinated muscle movements
Common (1% to 10%): Drowsiness
Frequency not reported: Sedation, somnolence, dizziness, confusion, extrapyramidal symptoms, lassitude, tremors, convulsive seizures, neuroleptic malignant syndrome[Ref]
Frequency not reported: Euphoria, dysphoria, agitation, transient hallucinations and disorientation
Frequency not reported: Confusion, disorientation, euphoria, nervousness, insomnia, excitation, catatonic-like states, hysteria, hallucinations, nightmares, agitation, paradoxical reactions, hyperexcitability[Ref]
Hyperexcitability and abnormal movements have been reported following a single dose of promethazine.[Ref]
Frequency not reported: Phlebitis, hypotension, tachycardia, bradycardia, palpitation, syncope, circulatory depression, shock, cardiac arrest, faintness
Frequency not reported: Tachycardia, bradycardia, increased or decreased blood pressure, faintness[Ref]
Frequency not reported: Visual disturbances
Frequency not reported: Blurred vision, diplopia
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Some side effects of Mepergan Fortis may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.
More about Mepergan Fortis (meperidine / promethazine)
- Side Effects
- During Pregnancy
- Dosage Information
- Drug Images
- Drug Interactions
- Support Group
- 2 Reviews – Add your own review/rating
- Drug class: narcotic analgesic combinations
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