Orphenadrine

Dosage Forms & Strengths

injectable solution

• 30mg/mL

tablet, extended release

• 100mg

Muscle Spasm & Pain

Indicated for muscle spasm and relief of discomfort associated with acute painful musculoskeletal conditions

100 mg PO q12hr OR

60 mg IV/IM q12hr (switch to PO as soon as possible)

Other Indications & Uses

Off-label: Leg cramps resistant to quinine, Parkinson's disease

Safety and efficacy not established

Caution; not recommended for use in elderly because of increased sedation and anticholinergic effects

Muscle spasm, relief of discomfort associated with acute painful musculoskeletal conditions

100 mg PO q12hr OR

60 mg IV/IM q12hr (switch to PO as soon as possible)

You should not use orphenadrine if you are allergic to it, or if you have:

• urination problems;

• an enlarged prostate;

• glaucoma;

• a stomach ulcer;

• a blockage in your stomach or intestines;

• trouble swallowing; or

• myasthenia gravis.

To make sure orphenadrine is safe for you, tell your doctor if you have:

• heart disease;

• a heart rhythm disorder;

• coronary artery disease; or

• if you also use a narcotic (opioid) medication.

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether orphenadrine passes into breast milk or if it could affect the nursing baby. Tell your doctor if you are breast-feeding.

Orphenadrine is not approved for use by anyone younger than 18 years old.

Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Orphenadrine may be habit-forming. Never share orphenadrine with another person, especially someone with a history of drug abuse or addiction. Keep the medication in a place where others cannot get to it. Selling or giving away this medicine is against the law.

Orphenadrine is usually taken 2 times per day, once in the morning and once in the evening. Follow your doctor's dosing instructions.

Do not crush, chew, or break an extended-release tablet. Swallow it whole.

Orphenadrine is only part of a complete program of treatment that may also include rest, physical therapy, or other pain relief measures.

Store orphenadrine at room temperature away from moisture, heat, and light. Keep the bottle tightly closed when not in use.

Keep track of the amount of medicine used from each new bottle. Orphenadrine is a drug of abuse and you should be aware if anyone is using your medicine improperly or without a prescription.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using orphenadrine and call your doctor at once if you have:

• a light-headed feeling, like you might pass out;

• painful or difficult urination;

• little or no urination;

• confusion, anxiety, agitation, tremors, hallucinations; or

• pounding heartbeats or fluttering in your chest.

Common side effects may include:

• dizziness, drowsiness, weakness;

• nausea, vomiting;

• dry mouth; or

• constipation.

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Solution, Injection, as citrate:

Norflex: 30 mg/mL (2 mL [DSC]) [contains sodium metabisulfite]

Generic: 30 mg/mL (2 mL)

Solution, Injection, as citrate [preservative free]:

Generic: 30 mg/mL (2 mL)

Tablet Extended Release 12 Hour, Oral, as citrate:

Generic: 100 mg

• Skeletal Muscle Relaxant

Muscle spasms:

Oral: 100 mg twice daily

IM, IV: 60 mg every 12 hours

AbobotulinumtoxinA: Anticholinergic Agents may enhance the anticholinergic effect of AbobotulinumtoxinA. Monitor therapy

Acetylcholinesterase Inhibitors: Anticholinergic Agents may diminish the therapeutic effect of Acetylcholinesterase Inhibitors. Acetylcholinesterase Inhibitors may diminish the therapeutic effect of Anticholinergic Agents. Monitor therapy

Aclidinium: May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

Alcohol (Ethyl): May enhance the CNS depressant effect of Orphenadrine. Avoid combination

Amantadine: May enhance the anticholinergic effect of Anticholinergic Agents. Monitor therapy

Amifampridine: May diminish the anticholinergic effect of Anticholinergic Agents. Anticholinergic Agents may diminish the therapeutic effect of Amifampridine. Monitor therapy

Anticholinergic Agents: May enhance the adverse/toxic effect of other Anticholinergic Agents. Monitor therapy

Azelastine (Nasal): CNS Depressants may enhance the CNS depressant effect of Azelastine (Nasal). Avoid combination

Brimonidine (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Cannabis: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Chlorphenesin Carbamate: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy

Cimetropium: Anticholinergic Agents may enhance the anticholinergic effect of Cimetropium. Avoid combination

CNS Depressants: May enhance the CNS depressant effect of Orphenadrine. Avoid combination

Dimethindene (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Dronabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Eluxadoline: Anticholinergic Agents may enhance the constipating effect of Eluxadoline. Avoid combination

Gastrointestinal Agents (Prokinetic): Anticholinergic Agents may diminish the therapeutic effect of Gastrointestinal Agents (Prokinetic). Monitor therapy

Glucagon: Anticholinergic Agents may enhance the adverse/toxic effect of Glucagon. Specifically, the risk of gastrointestinal adverse effects may be increased. Avoid combination

Glycopyrrolate (Oral Inhalation): Anticholinergic Agents may enhance the anticholinergic effect of Glycopyrrolate (Oral Inhalation). Avoid combination

Ipratropium (Oral Inhalation): May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

Itopride: Anticholinergic Agents may diminish the therapeutic effect of Itopride. Monitor therapy

Kava Kava: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy

Levosulpiride: Anticholinergic Agents may diminish the therapeutic effect of Levosulpiride. Avoid combination

Lofexidine: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Magnesium Sulfate: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

MetyroSINE: CNS Depressants may enhance the sedative effect of MetyroSINE. Monitor therapy

Minocycline: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Mirabegron: Anticholinergic Agents may enhance the adverse/toxic effect of Mirabegron. Monitor therapy

Nabilone: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Nitroglycerin: Anticholinergic Agents may decrease the absorption of Nitroglycerin. Specifically, anticholinergic agents may decrease the dissolution of sublingual nitroglycerin tablets, possibly impairing or slowing nitroglycerin absorption. Monitor therapy

OnabotulinumtoxinA: Anticholinergic Agents may enhance the anticholinergic effect of OnabotulinumtoxinA. Monitor therapy

Oxatomide: May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

Oxomemazine: May enhance the CNS depressant effect of CNS Depressants. Avoid combination

Paraldehyde: CNS Depressants may enhance the CNS depressant effect of Paraldehyde. Avoid combination

Piribedil: CNS Depressants may enhance the CNS depressant effect of Piribedil. Monitor therapy

Potassium Chloride: Anticholinergic Agents may enhance the ulcerogenic effect of Potassium Chloride. Management: Patients on drugs with substantial anticholinergic effects should avoid using any solid oral dosage form of potassium chloride. Avoid combination

Potassium Citrate: Anticholinergic Agents may enhance the ulcerogenic effect of Potassium Citrate. Avoid combination

Pramipexole: CNS Depressants may enhance the sedative effect of Pramipexole. Monitor therapy

Pramlintide: May enhance the anticholinergic effect of Anticholinergic Agents. These effects are specific to the GI tract. Consider therapy modification

Ramosetron: Anticholinergic Agents may enhance the constipating effect of Ramosetron. Monitor therapy

RimabotulinumtoxinB: Anticholinergic Agents may enhance the anticholinergic effect of RimabotulinumtoxinB. Monitor therapy

ROPINIRole: CNS Depressants may enhance the sedative effect of ROPINIRole. Monitor therapy

Rotigotine: CNS Depressants may enhance the sedative effect of Rotigotine. Monitor therapy

Rufinamide: May enhance the adverse/toxic effect of CNS Depressants. Specifically, sleepiness and dizziness may be enhanced. Monitor therapy

Secretin: Anticholinergic Agents may diminish the therapeutic effect of Secretin. Management: Avoid concomitant use of anticholinergic agents and secretin. Discontinue anticholinergic agents at least 5 half-lives prior to administration of secretin. Consider therapy modification

Selective Serotonin Reuptake Inhibitors: CNS Depressants may enhance the adverse/toxic effect of Selective Serotonin Reuptake Inhibitors. Specifically, the risk of psychomotor impairment may be enhanced. Monitor therapy

Tetrahydrocannabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Thalidomide: CNS Depressants may enhance the CNS depressant effect of Thalidomide. Avoid combination

Thiazide and Thiazide-Like Diuretics: Anticholinergic Agents may increase the serum concentration of Thiazide and Thiazide-Like Diuretics. Monitor therapy

Tiotropium: Anticholinergic Agents may enhance the anticholinergic effect of Tiotropium. Avoid combination

Tolperisone: May enhance the adverse/toxic effect of Muscle Relaxants (Centrally Acting). Management: Monitor for increased sedation or CNS effects if tolperisone is combined with other centrally acting muscle relaxants. Consider decreasing the tolperisone dose if these agents are combined. Consider therapy modification

Umeclidinium: May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

Animal reproduction studies have not been conducted.