Orphenadrine Citrate Description

Orphenadrine Citrate Injection is a sterile aqueous solution of orphenadrine citrate. It is intended for intravenous or intramuscular administration.

Orphenadrine citrate is the citrate salt of orphenadrine and occurs as a white, crystalline powder having a bitter taste. It is practically odorless, sparingly soluble in water and slightly soluble in alcohol. It has the following structural formula:

N,N-Dimethyl-2-[( o -methyl-?-phenylbenzyl)oxy]ethylamine Citrate (1:1).

Each mL contains: Orphenadrine Citrate 30 mg, Sodium Metabisulfite 0.91 mg, Sodium Chloride 2.9 mg, in Water for Injection q.s. Sodium Hydroxide and/or Hydrochloric Acid may have been used to adjust pH.

Orphenadrine Citrate Indications And Usage

Orphenadrine citrate is indicated as an adjunct to rest, physical therapy, and other measures for the relief of discomfort associated with acute, painful musculo-skeletal conditions. The mode of action of this drug has not been clearly identified, but may be related to its analgesic properties. Orphenadrine citrate does not directly relax tense skeletal muscles in man.

Orphenadrine Citrate Contraindications

Orphenadrine citrate is contraindicated in patients with glaucoma, pyloric or duodenal obstruction, stenosing peptic ulcers, prostatic hypertrophy or obstruction at the bladder neck, cardiospasm (megaesophagus) and myasthenia gravis.

Orphenadrine citrate is contraindicated in patients who have demonstrated a previous hypersensitivity to the drug.

Orphenadrine Citrate Side Effects

Contains Sodium Metabisulfite, a sulfite that may cause allergic-type reactions including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown and probably low. Sulfite sensitivity is seen more frequently in asthmatic than in nonasthmatic people.

Some patients may experience transient episodes of lightheadedness, dizziness or syncope.

Orphenadrine citrate may impair the ability of the patient to engage in potentially hazardous activities such as operating machinery or driving a motor vehicle; ambulatory patients should therefore be cautioned accordingly.

Usage In Pregnancy

Safe use of orphenadrine citrate has not been established with respect to adverse effects upon fetal development. Therefore, orphenadrine citrate should be used in women of childbearing potential and particularly during early pregnancy only when in the judgment of the physician the potential benefits outweigh the possible hazards.

Usage In Children

Safety and effectiveness in children have not been established; therefore, this drug is not recommended for use in the pediatric age group.

Orphenadrine Citrate Precautions

Confusion, anxiety and tremors have been reported in few patients receiving propoxyphene and orphenadrine concomitantly. As these symptoms may be simply due to an additive effect, reduction of dosage and/or discontinuation of one or both agents is recommended in such cases.

Orphenadrine citrate should be used with caution in patients with cardiac decompensation, coronary insufficiency, cardiac arrhythmias, and tachycardia.

Safety of continuous long term therapy with orphenadrine citrate has not been established. Therefore if orphenadrine citrate is prescribed for prolonged use, periodic monitoring of blood, urine, and liver function values is recommended.