| Stereochemistry | RACEMIC |
| Molecular Formula | C18H23NO |
| Molecular Weight | 269.3813 |
| Optical Activity | ( + / - ) |
| Defined Stereocenters | 0 / 1 |
| E/Z Centers | 0 |
| Charge | 0 |
SHOW SMILES / InChI
SMILES
CN(C)CCOC(C1=CC=CC=C1)C2=CC=CC=C2C
InChI
InChIKey=QVYRGXJJSLMXQH-UHFFFAOYSA-N
InChI=1S/C18H23NO/c1-15-9-7-8-12-17(15)18(20-14-13-19(2)3)16-10-5-4-6-11-16/h4-12,18H,13-14H2,1-3H3
| Molecular Formula | C18H23NO |
| Molecular Weight | 269.3813 |
| Charge | 0 |
| Count |
MOL RATIO
1 MOL RATIO (average) |
| Stereochemistry | RACEMIC |
| Additional Stereochemistry | No |
| Defined Stereocenters | 0 / 1 |
| E/Z Centers | 0 |
| Optical Activity | ( + / - ) |
Orphenadrine is an anticholinergic drug of the ethanolamine antihistamine class used to treat muscle pain and to help with motor control in Parkinson's disease but has largely been superseded by newer drugs. Orphenadrine binds and inhibits both histamine H1 receptors and NMDA receptors. It restores the motor disturbances induced by neuroleptics, in particular, the hyperkinesia. The dopamine deficiency in the striatum increases the stimulating effects of the cholinergic system. This stimulation is counteracted by the anticholinergic effect of orphenadrine. It may have a relaxing effect on skeletal muscle spasms and it has a mood elevating effect. Orphenadrine is indicated as an adjunct to rest, physical therapy, and other measures for the relief of discomfort associated with acute painful musculoskeletal conditions. Orphenadrine is an anticholinergic with a predominantly central effect and only a weak peripheral effect. In addition, it has mild antihistaminic and local anesthetic properties. Parkinson's syndrome is the consequence of a disturbed balance between cholinergic and dopaminergic neurotransmission in the basal ganglia caused by a decrease in dopamine. Orphenadrine restores the physiological equilibrium and has a favorable effect on the rigidity and tremor of Parkinson's disease and Parkinsonian syndromes. Adverse reactions of orphenadrine citrate are mainly due to the mild anticholinergic action of orphenadrine citrate and are usually associated with higher dosage. Dryness of the mouth is usually the first adverse effect to appear. When the daily dose is increased, possible adverse effects include tachycardia, palpitation, urinary hesitancy or retention, blurred vision, dilatation of pupils, increased ocular tension, weakness, nausea, vomiting, headache, dizziness, constipation, drowsiness, hypersensitivity reactions, pruritus, hallucinations, agitation, tremor, gastric irritation and rarely urticaria and other dermatoses
CNS Activity
Originator
Approval Year
Doses
AEs
Overview
| CYP3A4 | CYP2C9 | CYP2D6 | hERG |
|---|---|---|---|
OverviewOther
| Other Inhibitor | Other Substrate | Other Inducer |
|---|---|---|
Drug as perpetrator
Sourcing
PubMed
Patents
Sample Use Guides
Acute musculoskeletal conditions: 100 mg orally twice a day (morning and evening) or 60 mg by intramuscular or intravenous injection. May repeat every 12 hours.
Quinine-resistant leg cramps: 100 mg orally at bedtime.
Route of Administration:
Other
An aliquot (400 mkl) of the brain membrane suspension (0.14 mg of protein), 100 mkl of (-)3H-QNB (0.95 nM) (specific activity 46 Ci/mmol), and 50 mk1 of the competing drugs at various concentrations were preincubated for 10 min. and thereafter incubated for 60 min. at 25C in 50 mM Tris-HC1 buffer (PH 7.4). When binding to heart and lung membranes was studied, 500 nkl of homogenate (protein contents were 0.58 mg and 0.54 mg of rat heart and lung tissue and 0.63 mg of guinea pig lung tissue was added to tubes containing 500 mkl of 50 mM Tris-HC1 buffer (PH 7.4), 100 mk1 of (-)3H-QNB (final concentration 0.4 nM) and 100 mkl of buffer (total binding) or unlabeled Orphenadrine.
