Orphenadrine

Butamirate citrate Choline dihydrogen citrate Clomiphone dihydrogen citrate Orphenadrine citrate Perisoxal citrate Proxazole citrate Copper (powder)... 

Skeletal Muscle Relaxant Combinations Carisoprodol Compound—carisoprodol, aspirin Mexaphen—chlorzoxazone, acetaminophen Lobac—salicylamide, phenyltoloxamine, acetaminophen Norgesic Fbrte—orphenadrine citrate, aspirin, caffeine Norgesic—orphenadrine citrate, aspirin, caffeine Robaxisal—methocarbamol, aspirin Sodol Compound—carisoprodol, aspirin Soma Compound—carisoprodol, aspirin... 

C4H,N0 108-01-0) see Aclatonium napadisilate Bromazine Chloroquine Deanol acetamidobenzoate Diphenhydramine Medrylamine Orphenadrine Pirisudanol Quinisocaine Suxamethonium chloride Tetracaine Tromanladine... 

C14H14O 5472-13-9) see Tofenacin 2-methylbenzhydryl chloride (C]4Hi3C1 41870-52-4) see Orphenadrine methyl benzilate... 

Suggest a synthesis fpr the anti-Parkinson drug orphenadrine (23). 

Ethers are stable toward hydrolysis, yet are hydrolyzed under severe conditions of acidity and temperature. Furthermore, the presence of certain moieties can decrease the high stability of ethers. In the case of aminoalkyl benzhydryl ethers of the general structure (aryl)2CH-0-(CH2)n-NRR, the decrease in stability becomes marked enough to be of pharmaceutical and even pharmacological relevance. This structural motif is a component of various drugs, including some well-known antihistamines and anticholinergics, e.g., diphenhydramine, orphenadrine, and chlorphenoxamine. 

Fig. 11.2. Mechanism of proton-catalyzed, hydrolysis of aminoalkyl benzhydryl ethers 11.24, e.g., diphenhydramine (R = R = H), orphenadrine (R = 2-Me, R = H), and chlorphenoxamine...

Detailed kinetics investigations have shown that the reaction follows pseudo-first-order kinetics. A linear relationship exists between pH and log k (the log of the rate constant), such that log k decreases by 1.7 (i.e., tm increases by a factor of ca. 50) with each increase of one pH unit. For example, the tu2 value of diphenhydramine (11.24, R = R = H, Fig. 11.2) and orphenadrine (11.24, R = 2-Me, R = H) at pH 0 and 25° were found to be 550 and 460 min, respectively, from which f1/2 values of ca. 460 and 360 h could be calculated for pH 1. Each increase of 10° in temperature led to a decrease in the f/2 value of 3 - 4 h. Hence the tV2 value of diphenhydramine and orphenadrine in the stomach at 37°, assuming pH 1 and neglecting any effect caused by ionic strength, should be ca. 4 d. This is clearly too slow for any significant nonenzymatic formation of benzhydrol in the body (see below). 

Opticrom 27 Optimine 16 Oramorph SR 50 Organidin 39 Orgaran 27 Orlistat 53 Ornade Sbansule 79 Orphenadrine 54, 78 Ortho Tri-Cyclen 79 Ortho-Cept 79 Ortho-Cyclen 79 Ortho-Novum 79 Ortho-Novum 7/7/7 79 Orudis 43 Oruvail 43 Os-cal 20 Oseltamivir 54 Osmitrol 47 Ovcon 79 Ovral 79 Oxacillin 54... 

Sumatriptan is a serotonin (5HT ) agonist, which does not cause dry mouth. Trihexyphenidyl, cinnarizine, imipramine and orphenadrine all tend to cause antimuscarinic side-effects, including dry mouth, constipation, blurred vision and urinary retention. 

Sympathomimetics, such as dobutamine and isoprenaline, mimic the sympathetic system. Orphenadrine is an antimuscarinic drug acting as an antagonist to the parasympathetic system. 

One of the main side-effects of opioid analgesics, such as codeine and tramadol, is constipation. Amitriptyline (tricyclic antidepressant) and orphenadrine tend to have antimuscarinic properties, resulting in side-effects such as constipation. Senna is a stimulant laxative indicated in constipation. 

Bromocriptine is a dopamine agonist acting by direct stimulation of the dopamine receptors. In Parkinson s disease, it is reserved for use in patients who are intolerant to levodopa or in whom levodopa alone is not sufficient. Orphenadrine is an antimuscarinic indicated in Parkinson s disease. Antimuscarinics tend to be more effective than levodopa in targeting tremor rather than rigidity and bradykinesia. Moclobemide is an antidepressant referred to as a reversible monoamine oxidase inhibitor (RIAAA) type A. 

Co-careldopa is a combination of levodopa and the peripheral dopadecar-boxylase inhibitor. Co-careldopa is indicated in Parkinson s disease to improve bradykinesia and rigidity rather than tremor. Orphenadrine is an antimuscarinic agent indicated in patients with Parkinson s disease where tremor predominates. Trifluoperazine is a piperazine antipsychotic that should be used with caution in patients with Parkinson s disease as its use may exacerbate the condition. 

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