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Orphenadrine citrate injection

Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.



COMMON BRAND NAME(S): Flexor, Norflex, Orphenate


This medication is a skeletal muscle relaxant used to relieve pain and discomfort associated with musculoskeletal injuries and conditions.

How To Use

This medication is given by injection into a vein or muscle by a health care professional. It is usually given twice a day. Use this medication exactly as directed. Do not increase the dose or take it more often or continue taking this for longer than prescribed.

Side Effects

Stomach upset, headache, blurred vision, drowsiness, dizziness, lightheadedness, dry mouth, constipation, difficulty urinating or irritation at the injection site may occur. If any of these effects continue or become bothersome, inform your doctor. Notify your doctor immediately if you develop: rapid heart rate, fainting, fever, breathing difficulties, skin rash, mental confusion, depression. To avoid dizziness and lightheadedness when rising from a seated or lying position, get up slowly. Also limit your intake of alcoholic beverages which will aggravate these effects. Use caution performing tasks requiring alertness if this medication causes you to feel drowsy. If you notice other effects not listed above, contact your doctor or pharmacist.


This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: glaucoma, stomach/intestinal blockage (pyloric or duodenal obstruction), certain ulcers (peptic ulcers), enlarged prostate (prostatic hypertrophy), certain muscle diseases (e.g., myasthenia gravis), enlarged or blocked bladder, certain blockages of the esophagus (cardiospasm). Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney disease, heart disease, liver disease, any allergies (especially to sulfites). This medication should be used during pregnancy only if clearly needed. Discuss the risks and benefits with your doctor. It is not known if this medication appears in breast milk. Consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of any over-the-counter or prescription medication you may take, including: propoxyphene (a narcotic pain reliever). Avoid the use of alcohol while taking this medication since excessive drowsiness or depression can occur. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include irregular heart rate, fainting, loss of consciousness, and seizures.


This medication is used in addition to rest, physical therapy or other measures prescribed to relieve your condition. Since this medication may make you temporarily feel better, do not try to speed your recovery by exercising or lifting too soon. It may cause further muscle damage. Follow your doctors orders.

Missed Dose

If you miss a dose, use it as soon as remembered; do not use it if it is near the time for the next dose, instead, skip the missed dose and resume your usual dosing schedule. Do not "double-up" the dose to catch up.


Store at room temperature between 59 and 86 degrees F (15 to 30 degrees C) away from heat and light. Do not store in the bathroom.