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Orphenate Side Effects

Generic Name: orphenadrine

Note: This document contains side effect information about orphenadrine. Some of the dosage forms listed on this page may not apply to the brand name Orphenate.

For the Consumer

Applies to orphenadrine: oral tablet, oral tablet extended release

Other dosage forms:

Along with its needed effects, orphenadrine (the active ingredient contained in Orphenate) 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:


  • 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

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

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

Nervous system

Nervous system side effects have included headache, light-headedness, dizziness, drowsiness, syncope and tremor. Infrequently, elderly patients have experienced mental confusion.[Ref]


Ocular side effects have included blurred vision, dilatation of pupils, and increased ocular tension.[Ref]


Cardiovascular side effects have included tachycardia and palpitations.[Ref]


Genitourinary side effects have included urinary hesitancy and retention.[Ref]


Gastrointestinal side effects have included dry mouth, nausea, vomiting, and gastric irritation.[Ref]


Musculoskeletal side effects have included weakness.[Ref]


Dermatologic side effects have included pruritus, and rarely, urticaria and other dermatosis.[Ref]


Psychiatric side effects have included hallucinations and agitation.[Ref]


Hematologic side effects have included very rare cases of aplastic anemia, however, no causal relationship has been established.[Ref]


1. "Product Information. Norflex (orphenadrine)." 3M Pharmaceuticals, St. Paul, MN.

Further information

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.