|
|
|
|
|
Lipitor: profile and news
Myogen Reports 2005 Results 07 Mar 2006 Split the pill, halve the cost 07 Mar 2006 Trial project tests waters on latest pathology plan 07 Mar 2006 Should You Be Taking CoQ10? 07 Mar 2006 Yeast treatment may affect warfarin therapy Mar 2, 2006 Warfarin ups fracture risk Feb 4, 2006 Benefits of Self-Monitoring Warfarin Therapy Feb 2, 2006 Oscient Pharmaceuticals Reports Financial Results for Fourth ... Mar 6, 2006 Antiphospholipid Antibody Syndrome Feb 28, 2006 Japanese scientists develop new blood test device Mar 5, 2006 Scientists develop new blood test tool Mar 5, 2006 HemoSense Signs Agreement with Reliant to Distribute INRatio for ... Feb 28, 2006 Inadvertent toxic drug reaction in the management of atrial ... Feb 28, 2006 Splitting pills no longer a pain, firm says Mar 3, 2006 The new battle of the sexes Mar 3, 2006 New Oral Anticoagulants Show Promise Feb 14, 2006 Anti-Platelet Use Reduces Stroke Severity and Improves Outcomes in ... Feb 20, 2006 Ambrisentan ARIES-2 Data to Be Presented at ATS 2006 -- San Diego Mar 2, 2006 How can I prevent my children from becoming travel sick? Mar 2, 2006 Use of Emboli-Blocking Filters Increases, But Rigorous Data Are ... Feb 28, 2006 Blood Thinner Boosts Elderly Fracture Risk Feb 2, 2006 Anti-clotting therapy may reduce severity of stroke, study shows Feb 16, 2006 Astra Scraps Exanta Feb 14, 2006 Rat race: time is running out for the last rodent on Canna Feb 6, 2006 Self Monitoring Treatment May Save Lives Feb 3, 2006 'Pharmed' goats seek drug licence Feb 22, 2006 Music's started, no one's dancing Feb 8, 2006 US FDA warns Mayne Pharma on vitamin promotion Feb 7, 2006 Encysive Pharmaceuticals Reports Fourth Quarter and Year End 2005 ... Feb 13, 2006 HemoSense to Present at the Roth Capital Partners 18th Annual ... Feb 13, 2006 Arixtra Effective and Well Tolerated in Acutely Ill Medical ... Feb 14, 2006 Roth Capital Partners 18th Annual Growth Stock Conference ... Feb 17, 2006 Horror of Horrors! Feb 23, 2006 Self-Monitoring of Blood Drug Helps Patients Feb 2, 2006 Penn Study Identifies Patients Most At-risk For Secondary Strokes Feb 3, 2006 AGONY OF DRUG ERROR GRANNY, 80 Feb 24, 2006 Patients Capable Of Self-monitoring Their Anticoagulation Therapy ... Feb 9, 2006 Andrew Stephen Feb 16, 2006 The lowdown on Omega 3 fatty acids Feb 21, 2006 "Medical Food" Available for Management of Osteoarthritis Feb 21, 2006 Secondary Stroke Prevention Guidelines Call for Upgrade of TIA ... Feb 21, 2006 Pivotal Study Published in British Medical Journal Reports ... Feb 13, 2006 Armed robbery suspect sought Feb 1, 2006 Self-treatment 'can save 2,600 a year' Feb 2, 2006 AstraZeneca Withdraws Exanta Because of Liver Damage (Update5) Feb 14, 2006 Other information Indication For management as an adjunct to diet to reduce elevated total-C, LDL-C, apo B, and TG levels in patients with primary hypercholesterolemia and mixed dyslipidemia. Pharmacology Atorvastatin, a selective, competitive HMG-CoA reductase inhibitor, is used to lower cholesterol and triglycerides in patients with hypercholesterolemia and mixed dyslipidemia and in the treatment of homozygous familial hypercholesterolemia. Atorvastatin has a unique structure, long half-life, and hepatic selectivity, explaining its greater LDL-lowering potency compared to other HMG-CoA reductase inhibitors. Mechanism Of Action Atorvastatin selectively and competitively inhibits the hepatic enzyme hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase. As HMG-CoA reductase is responsible for converting HMG-CoA to mevalonate, this results in a decrease in mevalonate, a precursor of cholesterol, and a subsequent decrease in hepatic cholesterol levels and increase in uptake of LDL cholesterol. Drug Category Anticholesteremic Agents; HMG-CoA Reductase Inhibitors; ATC:C10AA05 Brand Names/Synonyms Atorvastatin; Atorvastatin Calcium; Atorvastatin Calcium Salt; Atorvastatin, Calcium Salt; CCRIS 7159; CI 981; Cardyl; HSDB 7039; Lipitor; Sotis; Torvast; Tozalip; Xavator Dosage Forms Tablets contain 10, 20, or 40mg atorvastatin Absorption Atorvastatin is rapidly absorbed after oral administration. The absolute bioavailability of atorvastatin (parent drug) is approximately 14% and the systemic availability of HMG-CoA reductase inhibitory activity is approximately 30%. Interactions -->Interactions for Atorvastatin: The risk of myopathy during treatment with drugs of this class is increased with concurrent administration of cyclosporine, fibric acid derivatives, niacin (nicotinic acid), erythromycin, azole antifungals. Antacid: When atorvastatin and MaaloxÒ TC suspension were coadministered, plasma concentrations of atorvastatin decreased approximately 35%. However, LDL-C reduction was not altered. Antipyrine: Because atorvastatin does not affect the pharmacokinetics of antipyrine, interactions with other drugs metabolized via the same cytochrome isozymes are not expected. Colestipol: Plasma concentrations of atorvastatin decreased approximately 25% when colestipol and atorvastatin were coadministered. However, LDL-C reduction was greater when atorvastatin and colestipol were coadministered than when either drug was given alone. Cimetidine: Atorvastatin plasma concentrations and LDL-C reduction were not altered by coadministration of cimetidine. Digoxin: When multiple doses of atorvastatin and digoxin were coadministered, steady-state plasma digoxin concentrations increased by approximately 20%. Patients taking digoxin should be monitored appropriately. Erythromycin: In healthy individuals, plasma concentrations of atorvastatin increased approximately 40% with coadministration of atorvastatin and erythromycin, a known inhibitor of cytochrome P450 3A4. Oral Contraceptives: Coadministration of atorvastatin and an oral contraceptive increased AUC values for norethindrone and ethinyl estradiol by approximately 30% and 20%. These increases should be considered when selecting an oral contraceptive for a woman taking atorvastatin. Warfarin: Atorvastatin had no clinically significant effect on prothrombin time when administered to patients receiving chronic warfarin treatment. Endocrine Function HMG-CoA reductase inhibitors interfere with cholesterol synthesis and theoretically might blunt adrenal and/or gonadal steroid production. Clinical studies have shown that atorvastatin does not reduce basal plasma cortisol concentration or impair adrenal reserve. The effects of HMG-CoA reductase inhibitors on male fertility have not been studied in adequate numbers of patients. The effects, if any, on the pituitary-gonadal axis in premenopausal women are unknown. Caution should be exercised if an HMG-CoA reductase inhibitor is administered concomitantly with drugs that may decrease the levels or activity of endogenous steroid hormones, such as ketoconazole, spironolactone, and cimetidine. CNS Toxicity Brain hemorrhage was seen in a female dog treated for 3 months at 120 mg/kg/day. Brain hemorrhage and optic nerve vacuolation were seen in another female dog that was sacrificed in moribund condition after 11 weeks of escalating doses up to 280 mg/kg/day. The 120 mg/kg dose resulted in a systemic exposure approximately 16 times the human plasma area-under-the-curve (AUC, 0-24 hours) based on the maximum human dose of 80 mg/day. A single tonic convulsion was seen in each of 2 male dogs (one treated at 10 mg/kg/day and one at 120 mg/kg/day) in a 2-year study. No CNS lesions have been observed in mice after chronic treatment for up to 2 years at doses up to 400 mg/kg/day or in rats at doses up to 100 mg/kg/day. These doses were 6 to 11 times (mouse) and 8 to 16 times (rat) the human AUC (0-24) based on the maximum recommended human dose of 80 mg/day. CNS vascular lesions, characterized by perivascular hemorrhages, edema, and mononuclear cell infiltration of perivascular spaces, have been observed in dogs treated with other members of this class. A chemically similar drug in this class produced optic nerve degeneration (Wallerian degeneration of retinogeniculate fibers) in clinically normal dogs in a dose-dependent fashion at a dose that produced plasma drug levels about 30 times higher than the mean drug level in humans taking the highest recommended dose. |
|
Home | About | Cancers | Treatment | Medications Copyright onconews.org 2005. All Rights Reserved. |