Nifedipine Diltiazem

Despite the growth in interest in calcium blockers, there are comparatively few calcium channel blocking agents currently in clinical use. These drugs are characterised by the fact that they belong to classes of compounds which are chemically unrelated like Diltiazem , Nifedipine , Verapamil , Fluspirilene and some others (Scheme 1). 

Calcium Channel Blockers. The calcium channel blockers work by blocking the influx of calcium, an excitatory ion, into the cell. The first calcium channel blocker, verapamil (Calan), was introduced in the 1960s. Others, including diltiazem, nifedipine, and nimodipine, are now available. The calcium channel blockers have been used to treat a variety of medical conditions including high blood pressure, cardiac pain (angina) and arrhythmias, migraines, seizure disorders, and premature labor. 

The main drngs nsed for myocardial ischema therapy and for relieving pain in angina pectoris are nitrates and nitrites (nitroglycerin, isosorbide dinitrate, and pentaerythritol tetranitrate) snbstances that snppress adrenergic systems of the heart—j3-adrenoblockers (atenolol, methoprolol, propranolol, and nadolol), and Ca + channel blockers (verapamil, diltiazem, nifedipine, and nicardipine) as well as a few older drugs, in particular papaverine and dipyridamole. 

Calcium channel blockers (eg, diltiazem, nifedipine, verapamil). 

Verapamil, diltiazem, and perhaps nicardipine (but not nifedipine) inhibit hepatic drug-metabolizing enzymes. Metabolism of diltiazem, nifedipine, verapamil, and probably other calcium channel blockers subject to induction and inhibition. 

Diltiazem Nifedipine Israel ipine Verapamil Amlodipine... 

Al-Humayyd, M.S. Effect of diltiazem, nifedipine and verapamil on the antinociceptive action of acetylsalicylic acid in mice, Gen. Pharmac.1991, 22, 121-125. 

Cyt 3A3/4 metabolizes clozapine, sertindole, quetiapine common substrates -tricyclic antidepressants, nefazodone, sertraline, carbamazepine, ethosuximide, terfenadine, benzodiazepines, diltiazem, nifedipine, verapamil, erythromycin, cyclosporine, lidocaine, quinidine, cisapride, paracetamol. Common inhibitors -nefazodone, fluvoxamine, fluoxetine, ketoconazole. 

CALCIUM CHANNEL BLOCKERS BUSULFAN t plasma concentrations of busulfan and t risk of toxicity of busulfan such as veno-ocdusive disease and pulmonary fibrosis, when co-administered with diltiazem, nifedipine or verapamil Due to inhibition of CYP3A4-mediated metabolism of busulfan by these calcium channel blockers. Busulfan clearance may be l by 25%, and the AUC of busulfan may t by 1500 p,mol/L Monitor clinically for veno-ocdusive disease and pulmonary toxicity in transplant patients. Monitor busulfan blood levels as AUC of below 1500 p,mol/L per minute tends to prevent toxicity... 

CALCIUM CHANNEL BLOCKERS IFOSFAMIDE i plasma concentrations of 4-hydroxyifosfamide, the active metabolite of ifbsfamide and risk of inadequate therapeutic response when it is co-administered with diltiazem, nifedipine or verapamil Due to inhibition of the isoenzymatic conversion to active metabolites by diltiazem Monitor clinically the efficacy of ifosfamide and t the dose accordingly... 

CALCIUM CHANNEL BLOCKERS TOREMIFENE t plasma concentrations of toremifene when is coadministered with diltiazem, nifedipine or verapamil Due to inhibition of CYP3A4-mediated metabolism of toremifene Clinical relevance is uncertain. Necessary to monitor for clinical toxicities... 

CALCIUM CHANNEL BLOCKERS CORTICOSTEROIDS 1. Antihypertensive effects of calcium channel blockers are antagonized by corticosteroids 2. t adrenal-suppressive effects of dexamethasone, methylpred-nisolone and prednisolone when co-administered with diltiazem, nifedipine or verapamil. This may t the risk of infections and produce an inadequate response to stress scenarios 1. Mineralocorticoids cause sodium and water retention, which antagonizes the hypotensive effects of calcium channel blockers 2. Due to inhibition of metabolism of these corticosteroids 1. Monitor BP at least weekly until stable 2. Monitor cortisol levels and warn patients to report symptoms such as fever and sore throat... 

DILTIAZEM, NIFEDIPINE, FELODIPINE, LACIDIPINE, LERCANIDIPINE, NICARDIPINE, NISOLDIPINE DIGOXIN Possible T plasma concentrations of digoxin These calcium channel blockers are thought to -l renal excretion of digoxin Monitor digoxin levels carefully... 

IMATINIB CALCIUM CHANNEL BLOCKERS t plasma concentrations of imatinib when co-administered with diltiazem, nifedipine and verapamil, t risk of toxicity (e.g. abdominal pain, constipation, dyspnoea) and of neurotoxicity (e.g. taste disturbances, dizziness, headache, paraesthesia, peripheral neuropathy) Due to inhibition of hepatic metabolism of imatinib by the CYP3A4 isoenzymes by diltiazem Monitor for clinical efficacy and for the signs of toxicity listed, along with convulsions, confusion and signs of oedema (including pulmonary oedema). Monitor electrolytes and liver function, and for cardiotoxicity... 

INSULIN CALCIUM CHANNEL BLOCKERS -DILTIAZEM, NIFEDIPINE Single case reports of impaired glucose intolerance requiring t insulin requirements with diltiazem and nifedipine Uncertain at present Evidence suggests that calcium channel blockers are safe in diabetics monitor blood glucose levels when starting calcium channel blockers... 

Benzodiazepines alprazolam, clonazepam, diazepam, midazolam, triazolam, zolpidem Calcium channel blockers diltiazem, nifedipine, nimodipine, verapamil Steroids androgens, estrogens, cortisol Others erythromycin, terfenadine, cyclosporine, dapsone, ketoconazole, lovastatin, lidocaine, alfentanil, amiodarone, astemizole, codeine, sildenafil... 

Mexiletine Progesterone Testosterone Sildenafil Trazodone Vineristine Zaleplon Zolpidem Amlodipine Diltiazem Nifedipine Verapamil... 

Calcium channel antagonists enhance vasodilation by blocking L-type Ca2+ channels in cardiac and vascular tissues. They are particularly effective for elderly and African American patients. Drugs considered are verapamil, diltiazem, nifedipine, and nimodipine. 

The precise mechanism and sight of action of most compounds categorized as calcium inhibitory compounds, therefore, remains obscure. Future refinements in experimental models and techniques will undoubtedly will lead to the classification of calcium inhibitory compounds based upon their primary mechanism of action and specific site(s) of action (extracellular vs. intracellar). Because of the uncertainty surrounding the precise mechanisms of action of calcium inhibitory compounds, I will describe their cardiac electrical and mechanical effects illuding when possible to those compounds that are believed to act l) competitively with Ca + for specific calcium channels (e.g., Co +, Mn +, La2+, etc.) 2) at the cardiac cell membrane and possibly by one of several intracellular mechanisms (e.g., verapamil, diltiazem, nifedipine) and 3) intracellularly (e.g., 2-n-propyl and 2-n-butyl MDI). 

In summary, compared to diltiazem, nifedipine, and perhexiline, verapamil demonstrates the most consistent results in the control of both experimental and clinical arrhythmias. 

Obviously the interference of antihypertensive agents with cellular lipid metabolism may modify the atherosclerotic risk of individuals. Therefore, the effects of the Ca2+ antagonists, such as verapamil, diltiazem, nifedipine, and p-blockers, such as propanolol and metapralol on low density lipoprotein (LDL) receptor activity, cholesterol esterification time, oleate incorporation in triglycerides and sterol synthesis were studied in freshly isolated human leukocytes and in HEP G2 cells (Hepatoma cells). 

Noninterfering aspirin, chloroquine, cyclosporin, diltiazem, nifedipine, prednisolone... 

Soares KV, McGrath jj. Diltiazem, nifedipine, nimodipine or verapamil for neuroleptic induced tardive dyskinesia. Cochrane Database Syst Rev 2000 2 CD000206. 

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