Zuellig Pharma
Full Prescribing Info
Orphenadrine citrate.
Orphenadrine citrate 100 mg in the form of slow release tablet.
Pharmacology: Pharmacodynamics: Orphenadrine citrate is salt form of orphenadrine. It acts in the central nervous system at the brainstem. It has no direct effect of muscle relaxation. In animal it inhibited specifically to reticular formation (substantia reticularis). Orphenadrine does not have myoneural block activity and had no effect on crossed extensor reflex. It is classified as anticholinergic skeletal muscle relaxant. It may involve with analgesic activity and/or muscle relaxation activity for skeletal muscle. Orphenadrine is o-methyl analog of diphenhydramine which is antihistamine without sedative effect. On the contrary, it stimulated central nervous system mildly.
Pharmacokinetics: Orphenadrine is readily absorbed from the gastrointestinal tract and is almost completely metabolized to at least eight metabolites. Orphenadrine and its metabolites are excreted from the body in the urine, with a half-life of 14 hours.
Relief of painful muscle spasm associated with fibrositis, whiplash injuries, torticollis, prolapsed intervertebral disc, strains, sprains and similar conditions. Has also been shown to be of value in tension headache and persistent hiccough.
Dosage/Direction for Use
100 mg twice daily. In severe cases, dosage may be increased to 300 mg in any 24 hours period. It is an oral dosage form. It can be taken anytime regardless meal. Taking this medicine before meal may help relieving dry mouth. If discomfort in the stomach occurs after taking the medicine, it is recommended to take medicine with meal.
Symptoms: Orphenadrine overdosage are excitement, confusion, delirium leading to coma. Convulsions and tachycardia with dilated pupils and urinary retention may occur.
Treatment: Gastric lavage should be carried out immediately regardless of the estimated ingested dose. Convulsion and delirium respond to relatively large doses of diazepam, preferably by mouth. Adequate hydration of the patient is important.
Orphenadrine shows some anticholinergic activity and should not be used in patients with glaucoma, prostatic hypertrophy or obstruction at the bladder neck, or myasthenia gravis.
Not applicable.
Special Precautions
Orphenadrine may impair the ability of the patient to engage in potentially hazardous activities such as operating machinery or driving a motor vehicle; ambulatory patient should therefore be cautioned accordingly. Orphenadrine citrates should be used with caution in patients with tachycardia, cardiac decompensation, coronary insufficiency, cardiac arrhythmias. Safety of continuous long-term therapy with orphenadrine has not been established. Therefore, if orphenadrine is prescribed for prolonged use, periodic monitoring of blood, urine and liver function is recommended.
Use in Pregnancy: Safe use in pregnancy has not been established, therefore the drug should not be used in pregnant women or those likely to become pregnant unless the expected benefits outweigh the potential risks.
Use in Lactation: Not applicable.
Use in Children: Not applicable.
Use In Pregnancy & Lactation
Pregnancy: Safe use in pregnancy has not been established, therefore the drug should not be used in pregnant women or those likely to become pregnant unless the expected benefits outweigh the potential risks.
Lactation: Not applicable.
Adverse Reactions
Side effects rarely occur at the recommended dosage. Those encountered are associated with anticholinergic activity and may include nausea, dry mouth, blurring of vision. Rarely, rash or drowsiness may occur. These symptoms disappear rapidly with a reduction in dosage or cessation of medication. No toxic effects have been observed.
Drug Interactions
The effects of antimuscarinic agents such as orphenadrine may be enhanced by other drugs with antimuscarinic properties such as amantadine, some antihistamines, butyrophenones and phenothiazines, and tricyclic antidepressants. The reduction in gastric motility caused by antimuscarinic agents may affect the absorption of other drugs.
Store below 30°C.
MIMS Class
ATC Classification
M03BC01 - orphenadrine (citrate) ; Belongs to the class of ethers. Used as centrally-acting muscle relaxants.
SR tab 100 mg (white embossed round and scored in half marked NX on one side and no marking on the other side) x 5 x 20's.
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