Note: This document contains side effect information about orphenadrine. Some dosage forms listed on this page may not apply to the brand name Norflex.
Applies to orphenadrine: oral tablet extended release. Other dosage forms:
- injection solution
Serious side effects of Norflex
Along with its needed effects, orphenadrine (the active ingredient contained in Norflex) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur while taking orphenadrine:
Rare
- Chest pain
- chills
- cough
- fever
- hallucinations (seeing, hearing, or feeling things that are not there)
- headache
- shortness of breath, troubled breathing, tightness in chest, and/or wheezing
- skin rash, hives, itching, or redness
- sores, ulcers, or white spots on lips or in mouth
- swollen and/or painful glands
- unusual bruising or bleeding
- unusual tiredness or weakness
Incidence not known
- Abdominal or stomach pain
- diarrhea
- fainting
- fast, pounding irregular heartbeat or pulse
- glaucoma
- joint or muscle pain
- nausea
- numbness or tingling of face, hands, or feet
- redness and soreness of eyes
- swelling of feet or lower legs
- vomiting
Get emergency help immediately if any of the following symptoms of overdose occur while taking orphenadrine:
Symptoms of Overdose
- Blurred vision
- confusion, delirium, or hallucinations
- constipation
- difficult urination
- drowsiness
- dry eyes, mouth, nose, or throat
- eye pain
- flushing or redness of face
- troubled breathing
Other side effects of Norflex
Some side effects of orphenadrine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.
Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common or rare
- Dizziness or lightheadedness
- excitement, irritability, nervousness, or restlessness
- headache
- muscle weakness
- unusually large pupils of eyes
Incidence not known
- Anxiety
- deep or fast breathing with dizziness
- itching skin
- mental confusion
- numbness of feet, hands and around mouth
- trembling or shaking of hands or feet shakiness in legs, arms, hands, or feet
For Healthcare Professionals
Applies to orphenadrine: compounding powder, injectable solution, oral tablet extended release.
General
The more commonly reported adverse reactions are due to the anticholinergic effects of this drug; dry mouth is usually the first adverse effect to appear.
Hypersensitivity
Rare (less than 0.1%): Anaphylaxis (with IM injection)
Frequency not reported: Hypersensitivity reactions
Nervous system
Frequency not reported: Headache, light-headedness, dizziness, drowsiness, syncope, tremor, sedation, convulsions, coordination difficulties[Ref]
Psychiatric
Rare (less than 0.1%): Memory disturbances
Frequency not reported: Hallucinations, agitation, euphoria, restlessness, mental confusion (especially elderly)[Ref]
Ocular
Frequency not reported: Blurred vision, dilatation of pupils, increased ocular tension, accommodation disorders[Ref]
Cardiovascular
Frequency not reported: Tachycardia, palpitations[Ref]
Gastrointestinal
Frequency not reported: Dry mouth, nausea, vomiting, constipation, gastric irritation[Ref]
Genitourinary
Frequency not reported: Urinary hesitancy, urinary retention[Ref]
Musculoskeletal
Frequency not reported: Weakness[Ref]
Dermatologic
Rare (less than 0.1%): Urticaria, other dermatoses
Frequency not reported: Pruritus[Ref]
Hematologic
Rare (less than 0.1%): Aplastic anemia[Ref]
