Orphenate (Injection)

Orphenadrine is used to help relax certain muscles in your body and relieve stiffness, pain, and discomfort caused by strains, sprains, or other injuries to your muscles. However, this medicine does not replace rest, exercise, physical therapy, or other treatments that your doctor may recommend for your medical issue.

Orphenadrine works in the central nervous system (CNS) to provide its muscle relaxant effects.

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

Your doctor will only give you a few doses of this medicine until your condition improves, and then you will be switched to an oral medicine that works the same way. If you have any concerns about this, talk to your doctor.

In deciding to use a medicine, you and your doctor need to consider the risks versus the benefits. For this medicine, think about the following:

Allergies

The dose of this medicine can vary for different patients. Follow your doctor's instructions or the directions on the label. The information below shows only the average doses. If your dose is different, do not change it unless your doctor says you can.

The amount of medicine you take depends on its strength. The number of doses you take each day, the time between doses, and how long you take the medicine depend on the medical issue you are treating.

Pediatric

There are no proper studies on how orphenadrine affects children. Its safety and effectiveness have not been established.

Geriatric

There is no information about how orphenadrine affects older patients. However, older adults are more likely to have heart, liver, or kidney issues related to age, which may require careful use of orphenadrine.

Breast Feeding

There are no adequate studies on the effects of this medication on infants when taken by breastfeeding women. Weigh the potential benefits against the risks before using this medication while breastfeeding.

Interactions with Medicines

Some medicines should not be used together at all, while others can be used together even if there might be an interaction. In these cases, your doctor might adjust the dose, or other precautions may be necessary. It's very important for your healthcare provider to know if you are taking any of the medicines listed below. The following interactions are highlighted for their potential significance but are not all-inclusive.

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

• Potassium Citrate

Using this medicine with any of the following medicines is usually not recommended, but might be necessary in some situations. If both medicines are prescribed together, your doctor may adjust the dose or frequency of one or both 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
• Levocetirizine
• Levorphanol
• Lofexidine
• Loxapine
• Magnesium Oxybate
• Meperidine
• Methacholine
• Methadone
• Metoclopramide
• Midazolam
• Morphine
• Morphine Sulfate Liposome
• Nalbuphine
• Olanzapine
• 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 increase the risk of certain side effects, but using both may be necessary for your treatment. If both medicines are prescribed, your doctor may adjust the dose or frequency of one or both medicines.

• Perphenazine

Interactions with Food/Tobacco/Alcohol

Some medicines should not be taken around mealtimes or with certain foods due to potential interactions. Using alcohol or tobacco with certain medicines may also lead to interactions. Talk to your healthcare provider about using this medicine with food, alcohol, or tobacco.

Other Medical Problems

Having other medical issues may affect the use of this medicine. Make sure to inform 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.

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 or nurse immediately if any of the following side effects occur:

Rare

• Cough
• Difficulty swallowing
• Dizziness
• Fast heartbeat
• Hives
• Itching
• Puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• Shortness of breath
• Skin rash
• Tightness in chest
• Unusual tiredness or weakness
• Wheezing

Incidence not known

• Abdominal or stomach pain
• Diarrhea
• Fast, pounding, or irregular heartbeat or pulse
• Fever
• Glaucoma
• Joint or muscle pain
• Nausea
• Numbness or tingling of face, hands, or feet
• Redness and soreness of eyes
• Shortness of breath
• Sores in mouth
• 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:

Incidence not known

• Anxiety
• Deep or fast breathing with dizziness
• Headache
• Irritability
• Itching skin
• Mental confusion
• Nervousness
• Numbness of feet, hands and around mouth
• Restlessness
• Trembling or shaking of hands or feet
• Shakiness in legs, arms, hands, or feet
• Unusually large pupils of eyes
• Weakness

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.

In the U.S.

• Antiflex
• Mio-Rel
• Norflex
• Orfro
• Orphenate

Available Dosage Forms:

• Solution

Therapeutic Class: Skeletal Muscle Relaxant, Centrally Acting

Pharmacologic Class: Antimuscarinic

A nurse or other trained health professional will give you this medicine. This medicine is given through a needle placed in one of your veins or into your muscle.