orphenadrine

Summary

Summary: A muscarinic antagonist used to treat drug-induced parkinsonism and to relieve pain from muscle spasm.

Top Publications

  1. Wiley J, Harvey S, Balster R, Nicholson K. Affinity and specificity of N-methyl- D-aspartate channel blockers affect their ability to disrupt prepulse inhibition of acoustic startle in rats. Psychopharmacology (Berl). 2003;165:378-85 pubmed
    ..Recently, a number of low-affinity NMDA channel blockers that exhibit minimal PCP-like effects in humans at therapeutic doses have been developed...
  2. Reidy G, Mehta I, Murray M. Inhibition of oxidative drug metabolism by orphenadrine: in vitro and in vivo evidence for isozyme-specific complexation of cytochrome P-450 and inhibition kinetics. Mol Pharmacol. 1989;35:736-43 pubmed
    The anti-parkinsonian agent orphenadrine has been shown to form an in vitro metabolic intermediate (MI) complex in hepatic microsomes isolated from phenobarbital (PB)-treated rats...
  3. Shama S. Spectrophotometric determination of phenylephrine HCl and orphenadrine citrate in pure and in dosage forms. J Pharm Biomed Anal. 2002;30:1385-92 pubmed
    ..rapid spectrophotometric methods have been estimated for the microdetermination of phenylephrine HCl (I) and orphenadrine citrate (II)...
  4. Abdul Baqi K. Objective high-frequency tinnitus of middle-ear myoclonus. J Laryngol Otol. 2004;118:231-3 pubmed
    ..Direct stimulation of the soft palate showed no evidence of palated myoclonus. Tympanometry confirmed rhythmic changes in the middle-ear compliance. The condition was effectively treated with a muscle relaxant (orphenadrine citrate).
  5. Barroso A, Lima V, Guzzo G, Moraes R, Vasconcellos M, Bezerra M, et al. Efficacy and safety of combined piroxicam, dexamethasone, orphenadrine, and cyanocobalamin treatment in mandibular molar surgery. Braz J Med Biol Res. 2006;39:1241-7 pubmed
    ..determine the efficacy and safety of the therapeutic combination of 10 mg piroxicam, 1 mg dexamethasone, 35 mg orphenadrine citrate, and 2...
  6. Guo Z, Raeissi S, White R, Stevens J. Orphenadrine and methimazole inhibit multiple cytochrome P450 enzymes in human liver microsomes. Drug Metab Dispos. 1997;25:390-3 pubmed
    The specificities of orphenadrine and methimazole on eight human liver P450 enzyme activities were evaluated by studying the extent of inhibition at different concentrations in two protocols: competitive inhibition and preincubation...
  7. Desaphy J, Dipalma A, De Bellis M, Costanza T, Gaudioso C, Delmas P, et al. Involvement of voltage-gated sodium channels blockade in the analgesic effects of orphenadrine. Pain. 2009;142:225-35 pubmed publisher
    b>Orphenadrine is a drug acting on multiple targets, including muscarinic, histaminic, and NMDA receptors. It is used in the treatment of Parkinson's disease and in musculoskeletal disorders...
  8. Altamura A, Mauri M, De Novellis F, Percudani M, Vampini V. Residual neuroleptic-induced parkinsonian symptoms in schizophrenia. A naturalistic study with orphenadrine. Pharmacopsychiatry. 1989;22:246-9 pubmed
    ..All patients had been treated continuously for the previous 10-12 weeks with haloperidol (HL) combined with orphenadrine (ORD). The dosages of HL and ORD remained unchanged for at least four weeks before the evaluations...
  9. Bersani G, Grispini A, Marini S, Pasini A, Valducci M, Ciani N. 5-HT2 antagonist ritanserin in neuroleptic-induced parkinsonism: a double-blind comparison with orphenadrine and placebo. Clin Neuropharmacol. 1990;13:500-6 pubmed
    ..In this double-blind comparative study with orphenadrine (150 mg daily p.o.) and placebo, ritanserin (30 mg daily p.o...

More Information

Publications62

  1. Fernandez Sanchez M, Diaz Trelles R, Groppetti A, Manfredi B, Brini A, Biella G, et al. Nefopam, an analogue of orphenadrine, protects against both NMDA receptor-dependent and independent veratridine-induced neurotoxicity. Amino Acids. 2002;23:31-6 pubmed
    ..While, nefopam structure resembles that of orphenadrine, an uncompetitive NMDA receptor antagonist, here we report that differently from orphenadrine, nefopam (100 ..
  2. Scholz E, Konrad F, Weiss D, Zitron E, Kiesecker C, Bloehs R, et al. Anticholinergic antiparkinson drug orphenadrine inhibits HERG channels: block attenuation by mutations of the pore residues Y652 or F656. Naunyn Schmiedebergs Arch Pharmacol. 2007;376:275-84 pubmed
    The anticholinergic antiparkinson drug orphenadrine is an antagonist at central and peripheral muscarinic receptors. Orphenadrine intake has recently been linked to QT prolongation and Torsade-de-Pointes tachycardia...
  3. Biella G, Groppetti A, Novelli A, Fernández Sánchez M, Manfredi B, Sotgiu M. Neuronal sensitization and its behavioral correlates in a rat model of neuropathy are prevented by a cyclic analog of orphenadrine. J Neurotrauma. 2003;20:593-601 pubmed
    ..Because nefopam is a known analgesic derivative of orphenadrine and of its congener diphenhydramine, both uncompetitive NMDA receptor antagonists, we tested the effect of ..
  4. Saracino M, Petio C, Vitali M, Franchini L, Raggi M. Determination of orphenadrine plasma levels using HPLC with diode array detection and a novel solid-phase extraction procedure in psychiatric patients. J Pharm Biomed Anal. 2009;50:501-6 pubmed publisher
    b>Orphenadrine is an antimuscarinic agent mainly used for the treatment of parkinsonism and to alleviate the neuroleptic syndrome induced by antipsychotic drugs...
  5. Glaser R, Donnell D, Maartmann Moe K. Solid-state structure of orphenadrine hydrochloride and conformational comparisons with diphenhydramine hydrochloride and nefopam hydrochloride. J Pharm Sci. 1992;81:858-62 pubmed
    The solid-state structure of (+-)-orphenadrine hydrochloride [(CH3)2NCH2CH2OCH(o-CH3C6H4)(Ph).HCl], a skeletal muscle relaxant drug, was determined by single-crystal X-ray diffraction analysis...
  6. Van Herreweghe I, Mertens K, Maes V, Ramet J. Orphenadrine poisoning in a child: clinical and analytical data. Intensive Care Med. 1999;25:1134-6 pubmed
    b>Orphenadrine is an anticholinergic drug used mainly in the treatment of Parkinson's disease. It has a peripheral and central effect and a known cardiotoxic effect when taken in large doses...
  7. Gibson W, Roques T, Young J. Modulation of antagonist binding to histamine H1-receptors by sodium ions and by 2-amino-2-hydroxymethyl-propan-1,3-diol HCl. Br J Pharmacol. 1994;111:1262-8 pubmed
    ..5 fold.7. It is concluded that Na+ can act as an allosteric effector of the binding of antagonists at the histamine HI-receptor. Tris HCl also appears to have an allosteric action at the H1-receptor...
  8. Gareri P, De Fazio P, Cotroneo A, Lacava R, Gallelli L, De Fazio S, et al. Anticholinergic drug-induced delirium in an elderly Alzheimer's dementia patient. Arch Gerontol Geriatr. 2007;44 Suppl 1:199-206 pubmed
    ..psychiatric assessment led to the diagnosis of melancholic depression and therapy with haloperidol 2mg/day, orphenadrine 100mg daily, amitriptyline 40 mg/day, lorazepam 2mg/day was started...
  9. Contin M, Riva R, Martinelli P, Procaccianti G, Albani F, Baruzzi A. Combined levodopa-anticholinergic therapy in the treatment of Parkinson's disease. Effect on levodopa bioavailability. Clin Neuropharmacol. 1991;14:148-55 pubmed
    The effect of chronic intake of the anticholinergic drug orphenadrine on the bioavailability of levodopa was studied in six patients with Parkinson's disease...
  10. Papadimitriou G, Theleritis C, Papageorgiou C, Kalogeromitros D, Syrigou E, Gregoriou S, et al. Acute adverse cutaneous reaction after the concomitant use of venlafaxine and orphenadrine citrate plus paracetamol in a depressed patient. J Eur Acad Dermatol Venereol. 2006;20:1019 pubmed
  11. Elghazali M, Wasfi I, Abdel Hadi A, Latum A. Pharmacokinetic, metabolism and withdrawal time of orphenadrine in camels (Camelus dromedarius) after intravenous administration. Res Vet Sci. 2008;85:563-9 pubmed publisher
    The pharmacokinetics of orphenadrine (ORPH) following a single intravenous (i.v.) dose was investigated in six camels (Camelus dormedarius)...
  12. van Gijn J. [Diagnostic image (17). Acute dystonia induced by prochlorperazine]. Ned Tijdschr Geneeskd. 2000;144:2496 pubmed
    ..Five hours after the last dose she developed dystonic posturing; she recovered rapidly after intramuscular injection of 40 mg orphenadrine.
  13. Sälinger D, Brückner R. The first asymmetric halogen/metal-exchange reaction: desymmetrization of alcohols with enantiotopic bromoarene substituents. Chemistry. 2009;15:6688-703 pubmed publisher
    ..The best ee/yield combination was obtained for the protonolysis furnishing monobromoalcohol (R)-2 (53 % ee, 51 % yield). The latter was converted into (R)-orphenadrine, an antihistaminic and anticholinergic drug.
  14. Desaphy J, Carbonara R, Costanza T, Conte Camerino D. Preclinical evaluation of marketed sodium channel blockers in a rat model of myotonia discloses promising antimyotonic drugs. Exp Neurol. 2014;255:96-102 pubmed publisher
    ..propafenone showed antimyotonic activity at doses similar to mexiletine (ED50 close to 5mg/kg); flecainide and orphenadrine showed greater potency (ED50 near 1mg/kg); lubeluzole and riluzole were the more potent (ED50 near 0.1mg/kg)...
  15. Sureda F, Gabriel C, Pallas M, Adan J, Martinez J, Escubedo E, et al. In vitro and in vivo protective effect of orphenadrine on glutamate neurotoxicity. Neuropharmacology. 1999;38:671-7 pubmed
    The anticholinergic drug orphenadrine is used in the treatment of Parkinson's disease. In this study we evaluate the neuroprotective effects of orphenadrine on excitotoxicity in vivo and in vitro...
  16. Treherne J, Young J. [3H]-(+)-N-methyl-4-methyldiphenhydramine, a quaternary radioligand for the histamine H1-receptor. Br J Pharmacol. 1988;94:797-810 pubmed
    ..6. The potential utility of [3H]-QMDP for studies of H1-receptors in the plasma membrane of cells in culture is discussed...
  17. Moberg E, Hagg E, Asplund K, Grankvist K. Misleading T3-test values in psychiatric patients treated with orphenadrine. Acta Med Scand. 1987;222:375-9 pubmed
    ..Of the 13 patients with increased T3-test values, 10 were on orphenadrine (Disipal) treatment or had recently stopped taking the drug...
  18. Darwish K, Salama I, Mostafa S, El Sadek M. Validated stability-indicating reversed-phase-HPLC method for simultaneous determination of orphenadrine citrate, caffeine and aspirin. Chem Pharm Bull (Tokyo). 2012;60:1426-36 pubmed
    ..high-performance liquid chromatographic method was developed for the simultaneous determination of orphenadrine citrate, caffeine and aspirin in presence of aspirin degradation products, orphenadrine citrate and caffeine ..
  19. Gjerden P, Slørdal L, Bramness J. The use of antipsychotic and anticholinergic antiparkinson drugs in Norway after the withdrawal of orphenadrine. Br J Clin Pharmacol. 2009;68:238-42 pubmed publisher
    ..The withdrawal of orphenadrine from the Norwegian market provided a possibility to investigate to what degree these alternative measures were ..
  20. Schifano F, Di Costanzo E. Excessive use of anticholinergic drugs in a sub-sample of Italian schizophrenics. Int J Clin Pharmacol Ther Toxicol. 1991;29:184-6 pubmed
    ..Ten point four percent of the sample (22 patients) took these drugs in amounts greater than those prescribed. Some possible explanations of this excessive use are discussed...
  21. McBride W, Hicks L. Acetylcholine and choline levels in rabbit fetuses exposed to anticholinergics. Int J Dev Neurosci. 1987;5:117-25 pubmed
    ..Thalidomide and the anticholinergics, scopolamine hydrobromide and orphenadrine hydrochloride, and doxylamine succinate, an antihistamine with secondary anticholinergic action, were ..
  22. Aglas F, Fruhwald F, Chlud K. [Results of efficacy study with diclofenac/orphenadrine infusions in patients with musculoskeletal diseases and functional disorders]. Acta Med Austriaca. 1998;25:86-90 pubmed
    ..a combination of the non-steroid antiphlogistic agent diclofenac (75 mg) and the muscle relaxing agent orphenadrine (30 mg) parenterally for 7 days...
  23. Morita R, Yafune A, Shiraki A, Itahashi M, Akane H, Nakane F, et al. Enhanced liver tumor promotion activity in rats subjected to combined administration of phenobarbital and orphenadrine. J Toxicol Sci. 2013;38:415-24 pubmed
    Phenobarbital (PB) and orphenadrine (ORPH) are cytochrome P450 (CYP) 2B inducers and have liver tumor-promoting effects in rats...
  24. Bramer T, Dew N, Edsman K. Catanionic mixtures involving a drug: a rather general concept that can be utilized for prolonged drug release from gels. J Pharm Sci. 2006;95:769-80 pubmed
    ..The drug compounds investigated were lidocaine, ibuprofen, naproxen, alprenolol, propranolol, and orphenadrine. Of the six drug molecules used in this study, five, both positively and negatively charged, were capable of ..
  25. Pubill D, Canudas A, Pallas M, Sureda F, Escubedo E, Camins A, et al. Assessment of the adrenergic effects of orphenadrine in rat vas deferens. J Pharm Pharmacol. 1999;51:307-12 pubmed
    The peripheral adrenergic effects of orphenadrine, an antiparkinsonian drug, have been evaluated in the rat vas deferens to investigate whether these properties are the same as those of other phencyclidine ligands...
  26. Casale R, Glynn C, Buonocore M. Reduction of spastic hypertonia in patients with spinal cord injury: a double-blind comparison of intravenous orphenadrine citrate and placebo. Arch Phys Med Rehabil. 1995;76:660-5 pubmed
    Spasticity is one of the major problems affecting the outcome of rehabilitation in paraplegic patients. Orphenadrine citrate possesses an effective muscle relaxant action in many pathologies...
  27. Fucci N, Romano B, Zirilli A. Acute intoxication with orphenadrine and clozapine. Forensic Sci Int. 2001;123:13-6 pubmed
    This report describes a fatal intoxication with two different drugs: clozapine and orphenadrine. A 38-year-old man was found dead in the bedroom of his residence...
  28. Czuczwar M, Cieszczyk J, Czuczwar K, KiÅ› J, Saran T, Turski W. Influence of orphenadrine upon the protective activity of various antiepileptics in the maximal electroshock-induced convulsions in mice. Pharmacol Rep. 2009;61:732-6 pubmed
    b>Orphenadrine is an anticholinergic drug used in the treatment of Parkinson's disease, and is also known to exert nonspecific antagonistic activity at the phencyclidine binding site of the N-methyl-D-aspartate (NMDA) receptor...
  29. Buhrich N, Weller A, Kevans P. Misuse of anticholinergic drugs by people with serious mental illness. Psychiatr Serv. 2000;51:928-9 pubmed
    ..Marginalized patients living in the community are vulnerable to the misuse of anticholinergic drugs...
  30. Ren S, Yang J, Kalhorn T, Slattery J. Oxidation of cyclophosphamide to 4-hydroxycyclophosphamide and deschloroethylcyclophosphamide in human liver microsomes. Cancer Res. 1997;57:4229-35 pubmed
    ..1 mM) and high (0.7 and 5 mM) concentrations of CY, respectively. Although orphenadrine inhibition was observed in human liver microsomes (which has been taken to indicate CYP2B6 catalysis), ..
  31. Treherne J, Stern J, Flack W, Young J. Inhibition by cations of antagonist binding to histamine H1-receptors. Agents Actions Suppl. 1991;33:271-6 pubmed
    ..Li+ also had a similar potency against the two ligands, but Na+ was a much more potent inhibitor of the binding of [3H] QMDP than that of [3H] mepyramine...
  32. Leurs R, Donnell D, Timmerman H, Bast A. Interaction of nefopam and orphenadrine with the cytochrome P-450 and the glutathione system in rat liver. J Pharm Pharmacol. 1989;41:388-93 pubmed
    Nefopam, a cyclic analogue of orphenadrine, exhibits a type I (substrate) and a type II (ligand) interaction with ferri-cytochrome P-450 in control and phenobarbitone induced rat hepatic microsomes respectively...
  33. Bambrick M, Wilson D. Recurrent neuroleptic malignant syndrome in a man with mild mental handicap. J Intellect Disabil Res. 1992;36 ( Pt 4):377-81 pubmed
    ..The possibility of NMS occurring in people with mental handicap, who have a high level of neuroleptic drug prescription, must be borne in mind...
  34. Nielsen A, Mors N. [Atypical acute dystonia]. Ugeskr Laeger. 1998;160:7441-2 pubmed
    ..We describe a case of acute dystonia with atypical onset without relation to changes in dosage and with laryngeal involvement with aphonia, but without dyspnoea...
  35. Rejdak K, Nieoczym D, Czuczwar M, Kis J, Wlaz P, Turski W. Orphenadrine induces secondarily generalized convulsive status epilepticus in rats. Brain Res Bull. 2011;84:389-93 pubmed publisher
    The current study was aimed to assess the convulsant potency of orphenadrine (ORPH) in rats together with a screen of different conventional antiepileptic drugs (AEDs) on their efficacy to suppress it...
  36. Mao Y, Hung D, Yang C, Wang J. Full recovery from a potentially lethal dose of orphenadrine ingestion using conservative treatment: a case report. Hum Exp Toxicol. 2010;29:961-3 pubmed publisher
    Intoxication by orphenadrine is uncommon. The clinical features consist of both central and peripheral anticholinergic effects. Ingestion of 2 to 3 g orphenadrine in an adult has been associated with fatality...
  37. Borsodi M, Nagy E, Darvas K. [Diclofenac/orphenadrine as a combined analgetic in post-operative relief of pain]. Orv Hetil. 2008;149:1847-52 pubmed publisher
    ..of combined infusion containing non-steroid anti-inflammation diclofenac and central muscle relaxant orphenadrine, and those of tramadol HCl, during postoperative pain relief after low and middle category operations...
  38. Guay D. Are there alternatives to the use of quinine to treat nocturnal leg cramps?. Consult Pharm. 2008;23:141-56 pubmed
    ..To review the efficacy and tolerability profiles of quinine in nocturnal and dialysis-associated leg cramps and to examine potential alternative agents...
  39. Malek J, Nedelová I, Lopourová M, Stefan M, Kostál R. [Diclofenac 75mg. and 30 mg. orfenadine (Neodolpasse) versus placebo and piroxicam in postoperative analgesia after arthroscopy]. Acta Chir Orthop Traumatol Cech. 2004;71:80-3 pubmed
    ..We used a new agent (Neodolpasse) based on diclophenac and orphenadine, and compared its efficacy with piroxicam and placebo...
  40. Yang K, Lee J, Lee M. Effects of CYP inducers and inhibitors on the pharmacokinetics of intravenous theophylline in rats: involvement of CYP1A1/2 in the formation of 1,3-DMU. J Pharm Pharmacol. 2008;60:45-53 pubmed
    ..In rats pretreated with 3-methylcholanthrene (3-MC), orphenadrine or dexamethasone (main inducers of CYP1A1/2, CYP2B1/2 and CYP3A1/2, respectively, in rats), the time-averaged ..
  41. Rossi B, Vignocchi G, Siciliano G, Risaliti R. Effects of anticholinergic agents on the excitability of the blink reflex in Meige syndrome. Eur Neurol. 1989;29:281-3 pubmed
    Blink reflex recovery cycle, before and after acute administration of orphenadrine chlorhydrate, was tested in Meige syndrome...
  42. Danze L, Langdorf M. Reversal of orphenadrine-induced ventricular tachycardia with physostigmine. J Emerg Med. 1991;9:453-7 pubmed
    ..tonic-clonic seizures, and sustained ventricular tachycardia following ingestion of an unknown quantity of orphenadrine (Norflex)...
  43. Hannak D, Scharbert F, Kattermann R. Stepwise binary gradient high-performance liquid chromatographic system for routine drug monitoring. J Chromatogr A. 1996;728:307-10 pubmed
    ..Three examples are shown: Amiodarone, Indometacine and Thiopental. New applications to test for other substances can be transferred to an isocratic system after a complete MTSS gradient run...
  44. Coelho C, Figueiredo R, Frank E, Burger J, Schecklmann M, Landgrebe M, et al. Reduction of tinnitus severity by the centrally acting muscle relaxant cyclobenzaprine: an open-label pilot study. Audiol Neurootol. 2012;17:179-88 pubmed publisher
    ..Cyclobenzaprine at high (30 mg) and low doses (10 mg), orphenadrine (100 mg), tizanidine (24 mg) and eperisone (50 mg) were administered to a maximum of 20 patients per group over ..
  45. Rizzatti Barbosa C, Martinelli D, Ambrosano G, de Albergaria Barbosa J. Therapeutic response of benzodiazepine, orphenadrine citrate and occlusal splint association in TMD pain. Cranio. 2003;21:116-20 pubmed
    ..ordered association of occlusal splint therapy (S), nonsteroid anti-inflammatory with a muscle-relaxant drug (orphenadrine citrate) (O), and an anxiety-relief drug (benzodiazepine) (B), to ease painful TMD muscle symptoms...
  46. Wang X, Black L. Ex vivo percutaneous absorption of ketamine, bupivacaine, diclofenac, gabapentin, orphenadrine, and pentoxifylline: comparison of versatile cream vs. reference cream. Int J Pharm Compd. 2013;17:520-5 pubmed
    ..a set of six model drugs (ketamine hydrochloride, bupivacaine hydrochloride, diclofenac sodium, gabapentin, orphenadrine citrate, pentoxifylline) from two popular formulations for topically applied compounding preparations...
  47. Contin M, Riva R, Albani F, Baruzzi A. Simple and rapid GLC method for the determination of orphenadrine in human plasma. Biomed Chromatogr. 1987;2:193-4 pubmed
    A rapid and specific method has been developed for the determination of orphenadrine concentration in plasma...
  48. Hunskaar S, Rosland J, Hole K. Mechanisms of orphenadrine-induced antinociception in mice: a role for serotonergic pathways. Eur J Pharmacol. 1989;160:83-91 pubmed
    The possible involvement of central serotonergic pathways in the mechanism of action of orphenadrine citrate was investigated in male albino mice...
  49. Roos P. Common multiple interactions of tricyclic anti-depressants and orphenadrine with liver microsomal cytochrome P450 enzymes of the rat. Xenobiotica. 1999;29:629-40 pubmed
    ..It might be pharmacologically important that the dimethylamino compounds are demethylated in vivo by cytochromes P450 giving rise to more potent P450 inhibitors compared with the parent compounds...
  50. Ekins S, VandenBranden M, Ring B, Wrighton S. Examination of purported probes of human CYP2B6. Pharmacogenetics. 1997;7:165-79 pubmed
    ..b>Orphenadrine (ORP), a reported specific CYP2B6 inhibitor, was a less potent inhibitor of 7-HFC formation by microsomes from ..
  51. Gombotz H, Lochner R, Sigl R, Blasl J, Herzer G, Trimmel H. Opiate sparing effect of fixed combination of diclophenac and orphenadrine after unilateral total hip arthroplasty: A double-blind, randomized, placebo-controlled, multi-centre clinical trial. Wien Med Wochenschr. 2010;160:526-34 pubmed publisher
    ..This study demonstrates that Neodolpasse(®) Infusion Solution significantly reduces PCA analgesic requirements without compromising analgesic effectiveness and safety in THA patients...
  52. Gjerden P, Slørdal L. [Clinical pharmacology of anticholinergic antiparkinson agents. A review with emphasis on acute toxicity]. Tidsskr Nor Laegeforen. 1998;118:53-5 pubmed
    ..b>Orphenadrine dominates quantitatively among these drugs in Norway, presumably because it is assumed to carry a lower risk of ..
  53. Murray M, Fiala Beer E, Sutton D. Upregulation of cytochromes P450 2B in rat liver by orphenadrine. Br J Pharmacol. 2003;139:787-96 pubmed
    1 The alkylamine drug orphenadrine (ORPH) is an inducer and inhibitor of the microsomal cytochrome P450 (CYP) system in mammals. This study evaluated the selectivity of CYP induction by ORPH in rat liver...