Interactions between drugs

Patients with epilepsy often have comorbid disease states. Disorders such as chronic headaches and asthma are frequent problems. For patients who also have asthma, care must be taken to identify drug interactions between AEDs... 

Sirolimus is currently the only FDA-approved ToR inhibitor. One of its derivatives, everolimus, is in phase III clinical trials and has been approved for use in some European countries.30 Sirolimus is a macrolide antibiotic that has no effect on cal-cineurin phosphatase.11,31,32 Sirolimus inhibits T cell activation and proliferation by binding to and inhibiting the activation of the mammalian ToR, which suppresses cellular response to IL-2 and other cytokines (i.e., IL-4 and IL-15J.11,31 Studies have shown that sirolimus may be used safely and effectively with either cyclosporine or tacrolimus as a replacement for either azathioprine or mycophenolate mofetil.33 However, when using both sirolimus and cyclosporine as part of a patient s immunosuppressant therapy, because of a drug interaction between the two resulting in a marked increase in sirolimus concentrations, it is recommended to separate the sirolimus and cyclosporine doses by at least 4 hours. Sirolimus also can be used as an alternative agent for patients who do not tolerate calcineurin inhibitors due to nephrotoxicity or other adverse events.34... 

New York State Department of Health AIDS Institute. Drug-Drug Interactions Between HAART, Medications Used in Substance Use Treatment, and Recreational Drugs. 2005. Available at www.hivguidelines.org... 

Xu, G. (2004). Drug-drug interaction between herb medicine and western medicine. Chinese Remedies and Clinics, 4(3), 236-7. 

Dickinson BD, Altman RD, Nielsen NH, Sterling ML Council on Scientific Affairs, American Medical Association Drug interactions between oral contraceptives and antibiotics. Obstet Gynecol 2001 98 853-860. 

Egnell, A.-C., Houston, B. and Boyer, S. (2003) in vivo CYP3A4 heteroactivation is a possible mechanism for the drug interaction between felbamate and carbamazepine. The Journal of Pharmacology and Experimental Therapeutics, 305, 1251-1262. 

Eerslew KE, Hagardom AN, Harlan GC, McCormick WE. 1998. A fatal drug interaction between clozapine and fluoxetine. J Forensic Sci 43 1082. 

Tegretol consists of carbamazepine, which is an anti-epileptic drug. There is a clinically significant drug interaction between carbamazepine and clarithromycin (macrolide antibacterial agent) resulting in higher plasma concentrations of carbamazepine. 

Venlafaxine is metabolized to its active metabolite, ODV, by cytochrome P-450 2D6. Therefore, the potential exists for a drug interaction between venlafaxine and drugs that inhibit this isoenzyme. 

Sildenafil has other minor adverse effects, such as headache, nasal congestion, and flushing. There are no clinically significant drug interactions between sildenafil and apomorphine. Apomorphine, like sildenafil, is orally active. However, unlike sildenafil, it exerts its action through the central nervous system. Apomorphine can produce dizziness, nausea, pallor, and hypotension, and in the presence of ethanol, it purportedly increases... 

The prevalence of complementary and alternative medication (CAM) is increasing among older adults. In a recent report, nearly two thirds of ambulatory elderly used at least one form of CAM, but much of CAM use was unrecognized by physicians, CAMS have been associated with adverse events (Table 9) and important drug interactions between CAMs and conventional drug therapies have been... 

Dmg interactions Drug interactions between Neupogen and other drugs have not been fully evaluated. Drugs that may potentiate the release of neutrophils from bone marrow, such as lithium, should be used with caution. 

Barone GW, Gurley BJ, Ketel BL, Lightfoot ML, Abul-Ezz SR. Drug interaction between St. John s wort and cyclosporine. Ann Pharmacother 2000 34(9) 1013-1016. 

Katial RK, Stelzle RC, Bonner MW, Marino M, Cantilena LR, Smith LJ. A drug interaction between zafirlukast and theophylline. Arch Intern Med 1998 158(15) 1713-1715. 

There have been reports of a serious drug interaction between cyclosporine and the herbal dietary supplement, St. John s wort . This interaction has been reported to produce a marked reduction in the blood concentrations of cyclosporine, resulting in subtherapeutic levels, rejection of transplanted organs, and graft loss ... 

Williamson EM. Drug interactions between herbal and prescription medicines. Drug Safety 2003 26(15) 1075-1092. 

Up to 2001, AERS indicated up to 39 case reports of possible drug interactions between St. John s wort and a prescription drug. In these case reports, the potential drug interactions occurred mostly with oral contraceptives, antidepressants, cyclosporine, and sildenafil. All cases were reported between 1997 and 2000. Most of the reported cases were in females (24),... 

Potential drug interaction between sertraline and St. John s wort cannot be ruled out in one case that experienced manic depressive disorder symptoms one to two weeks after St. John s wort was started into sertraline therapy. The patient was treated with an antipsychotic and has had no problems after discontinuing St. John s wort and decreasing the sertraline dose. 

Lehmann, K.A., Kriegel, R., Ueki, M. Clinical relevance of drug interactions between opiates and calcium channel blockers, Anaesthesist 1989, 38, 110-115. 

Wilbur K, Ensom MH. Pharmacokinetic drug interactions between oral contraceptives and second-generation anticonvulsants. Clin Pharmacokinet 2000 38(4) 355-65. 

Komatsu K, Ito K, Nakajima Y, Kanamitsu S, Imaoka S, Funae Y, Green CE, Tyson CA, Shimada N, Sugiyama Y. Prediction of in vivo drug-drug interactions between tolbutamide and various sulfonamides in humans based on in vitro experiments. Drug Metab Dispos 2000 28(4) 475-81. 

Lin JC, Ito MK. A drug interaction between troglitazone and simvastatin. Diabetes Care 1999 22(12) 2104-6. 

Reyderman L, Kosoglou T, Statkevich P, Pember L, Boutros T, Maxwell SE, Affrime M, Batra V. Assessment of a multiple-dose drug interaction between ezetimibe, a novel selective cholesterol absorption inhibitor and gemfibrozil. International J Clin Pharmacol Ther 2004 42(9) 512-8. 

Balmelli N, Domine F, Pfisterer M, Krahenbuhl S, Marsch S. Fatal drug interaction between cholestyramine and phenprocoumon. Eur J Intern Med 2002 13(3) 210-1. 

Based on case reports or small studies, the potential for drug interactions between macrolides and lovastatin should be considered (17). 

A potential drug interaction between simvastatin and danazol, causing rhabdomyolysis and acute renal insufficiency, has been reported (43). Rhabdomyolysis can occur with all statins when they are used alone and particularly when they are combined with other drugs that are themselves myotoxic or that increase the concentration of the statin. Statins are particularly susceptible to the latter effect because of their metabolism by the CYP450 system and their low oral systemic availability. 

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