Pronunciation:

or-FEN-a-dreen

Brand Names:

• Norflex

Dosage Forms:

• Tablet, Extended Release

Classifications:

Therapeutic—

Skeletal Muscle Relaxant, Centrally Acting

Pharmacologic—

Antimuscarinic

Uses of This Medicine:

Orphenadrine is used to help relax certain muscles in your body and relieve the stiffness, pain, and discomfort caused by strains, sprains, or other injury to your muscles. One form of orphenadrine is also used to relieve trembling caused by Parkinson's disease. However, this medicine does not take the place of rest, exercise or physical therapy, or other treatment that your doctor may recommend for your medical problem.

Orphenadrine acts in the central nervous system (CNS) to produce its muscle relaxant effects. Orphenadrine also has other actions (anticholinergic) that produce its helpful effects in Parkinson's disease. Orphenadrine's CNS and anticholinergic actions may also be responsible for some of its side effects.

This medicine is available only with your doctor's prescription.

Before Using This Medicine:

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies—

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Children—

Appropriate studies have not been performed on the relationship of age to the effects of orphenadrine in the pediatric population. Safety and efficacy have not been established .

Older adults—

No information is available on the relationship of age to the effects of orphenadrine in geriatric patients. However, elderly patients are more likely to have age-related heart, liver, or kidney problems which may require caution in patients receiving orphenadrine .

Breast-feeding—

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Other medicines—

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

• Potassium Citrate

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Alfentanil
• Alprazolam
• Amantadine
• Amifampridine
• Benzhydrocodone
• Bromazepam
• Buprenorphine
• Butorphanol
• Calcium Oxybate
• Cannabidiol
• Cannabis
• Cetirizine
• Clobazam
• Clonazepam
• Clozapine
• Codeine
• Daridorexant
• Dexmedetomidine
• Dihydrocodeine
• Donepezil
• Doxylamine
• Esketamine
• Fentanyl
• Flibanserin
• Gabapentin
• Gabapentin Enacarbil
• Glucagon
• Glycopyrrolate
• Glycopyrronium Tosylate
• Hydrocodone
• Hydromorphone
• Ketamine
• Lacosamide
• Lemborexant
• LetibotulinumtoxinA-wlbg
• Levocetirizine
• Levorphanol
• Lofexidine
• Loxapine
• Magnesium Oxybate
• Meperidine
• Methacholine
• Methadone
• Metoclopramide
• Midazolam
• Morphine
• Morphine Sulfate Liposome
• Nalbuphine
• Olanzapine
• Oliceridine
• Oxycodone
• Oxymorphone
• Pentazocine
• Phenobarbital
• Potassium Oxybate
• Pregabalin
• Primidone
• Quetiapine
• Remifentanil
• Remimazolam
• Revefenacin
• Ropeginterferon Alfa-2b-njft
• Scopolamine
• Secretin Human
• Sodium Oxybate
• Sufentanil
• Tapentadol
• Tiotropium
• Topiramate
• Tramadol
• Trazodone
• Zolpidem
• Zuranolone

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Perphenazine

Other interactions—

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other medical problems—

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

• Enlarged esophagus or
• Enlarged prostate or
• Glaucoma or
• Intestinal blockage or
• Myasthenia gravis or
• Stomach ulcer or
• Urinary tract blockage—Orphenadrine should not be used in patients with these conditions .

• Heart problems (e.g., fast or irregular heartbeats, heart failure)—Use with caution. Orphenadrine may worsen these conditions .

Proper Use of This Medicine:

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

Dosing—

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For oral dosage form (extended-release tablets):
  • For relaxing stiff, sore muscles:
    • Adults and teenagers—100 milligrams (mg) two times a day, one tablet each in the morning and evening.
    • Children—Use and dose must be determined by your doctor .
• For oral dosage form (tablets):
  • For relaxing stiff, sore muscles and for Parkinson's disease:
    • Adults—50 milligrams (mg) three times a day.
    • Children—Use and dose must be determined by your doctor.

Missed dose—

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions While Using This Medicine:

It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects .

Orphenadrine may cause a serious type of allergic reaction called anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Check with your doctor right away if you have a rash; itching; swelling of the face, tongue, and throat; trouble with breathing; or chest pain after using this medicine .

This medicine may cause some people to become dizzy, lightheaded, faint, or less alert than they are normally. It may also cause muscle weakness in some people. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or are not alert and able to see well.

This medicine may add to the effects of alcohol and other CNS depressants (medicines that slow down the nervous system, possibly causing drowsiness). Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or narcotics; barbiturates; medicine for seizures; other muscle relaxants; or anesthetics, including some dental anesthetics. Do not drink alcoholic beverages, and check with your doctor before taking any of the medicines listed above, while you are using this medicine.

Orphenadrine may cause dryness of the mouth. For temporary relief, use sugarless candy or gum, melt bits of ice in your mouth, or use a saliva substitute. However, if dry mouth continues for more than 2 weeks, check with your dentist. Continuing dryness of the mouth may increase the chance of dental disease, including tooth decay, gum disease, and fungus infections.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements. .

Side Effects of This Medicine:

Along with its needed effects, a medicine 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:

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:

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 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

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.