Verapamil hydrochloride

Verapamil. Verapamil hydrochloride (see Table 1) is a synthetic papaverine [58-74-2] C2qH2 N04, derivative that was originally studied as a smooth muscle relaxant. It was later found to have properties of a new class of dmgs that inhibited transmembrane calcium movements. It is a (+),(—) racemic mixture. The (+)-isomer has local anesthetic properties and may exert effects on the fast sodium channel and slow phase 0 depolarization of the action potential. The (—)-isomer affects the slow calcium channel. Verapamil is an effective antiarrhythmic agent for supraventricular AV nodal reentrant arrhythmias (V1-2) and for controlling the ventricular response to atrial fibrillation (1,2,71—73). 

Verapamil. Verapamil hydrochloride is a pbenyl alkyl amine and is considered the prototype of the Class I calcium channel blockers. Verapamil is also a potent inhibitor of coronary artery spasm and is useful in Prinzmetal s angina and in unstable angina at rest. Verapamil produces negative chronotropic and inotropic effects. These two actions reduce myocardial oxygen consumption and probably account for the effectiveness of verapamil in chronic stable effort angina (98,99). Moreover, verapamil is an effective antihypertensive agent. 

Tarka (Knoll)-comb. with verapamil hydrochloride Udramil (Hoechst Marion Roussel Pohl-Boskamp)-comb. with verapamil hydrochloride... 

Verapamil Hydrochloride Verelan 120, 180, 240, 360 mg extended-release capsules... 

VERAPAMIL HYDROCHLORIDE Avo d verapamil in patients with severe left ventricular dysfunction (eg, ejection fractions less than 30%) or moderate to severe symptoms of cardiac failure and in patients with any degree of ventricular dysfunction if they are receiving a beta-adrenergic blocker. 

CLARINEX (Sobering) (desloratadine) tablets, syrup. Reditabs tablets August 2004 labeling COVERA-HS (Searle) (verapamil hydrochloride) extended-release tablets July 2003 labeling... 

Similar labeling language also in the labeling of ISOPTIN SR (Abbott) (verapamil HCl) sustained release oral tablets July 2003 and VERELAN PM capsules (Schwarz) (verapamil hydrochloride) extended-release capsules controlled-onset, March 2003. 

The product used was a hard gelatin capsule, size 0 (Posilok, Elanco), containing coated verapamil hydrochloride pellets (100 mg of verapamil hydrochloride) and coated barium sulphate pellets. 

The verapamil pellets contained equal parts of verapamil hydrochloride (Fermion) and lactose (Ph. Eur.) plus 4% of gelatin as a binder. They were coated using a fluidized bed technique (Aeromatic Strea 1, Aeromatic AG). The coat consisted of ethyl cellulose (Ethocel N-50), Hercules) and 20% of dibutyl sebacate (E. Merck) as a plasticizer. The calculated amount of coating in the pellets was 10%. The density of the verapamil pellets was 1.13. The in vitro dissolution pattern was determined according to the USP paddle method 50% of the drug was dissolved at 4.2 h. 

Synthesis of 62 commenced from verapamil hydrochloride, which has been O-demethylated by heating in aqueous 48% HBr (equation 26). 

Christrup, L.L., et al. 1990. Relative bioavailability of (+/—)-verapamil hydrochloride administered in tablets and chewing gum. Acta Pharm Nord 2 371. 

P. M. Lacroix, S. J. Graham, and E. G. Lovering, High-performance liquid chromatography method for the assay of verapamil hydrochloride and related compounds in raw materials, J. Pharm. Biomed. Anal., 9 119 (1992). 

Aminophylline Aminophylline should not be mixed with acidic drugs, as it becomes precipitated if the pH of the final solution falls below pH 8. Mixture with glucose may increase the pH above 10 where proteins, such as insulin and erythromycin, are unstable. Some drugs that are incompatible with aminophylline include amiodarone, benzylpenicillin potassium, cisatracurium, ceftazidime, ceftriaxone, dobutamine, tetracycline hydrochloride, verapamil hydrochloride, warfarin sodium, and vitamin B and C injection. Alcohol-free theophylline should be stored in amber-colored containers maximum care must be taken to protect it against exposure to light.92-94... 

Amrinone lactate is physically and chemically incompatible with alkaline solutions. Pharmaceuticals that are incompatible include digoxin, potassium chloride, procainamide hydrochloride, propranolol hydrochloride, verapamil hydrochloride, sodium chloride, and glucose solutions containing frusemide.101... 

Verapamil hydrochloride is incompatible with alkaline preparations and drugs such as aminophylline, nafcillin sodium, and sodium bicarbonate.128129... 

Loxapine Succinate 466.0 Mebeverine Hydrochloride 491.1 Verapamil Hydrochloride... 

The phase diagrams below highlight two typical cases, the first where the eutectic point E is close to the racemate, and the second where the eutectic approaches the single enantiomer as shown in Fig. 18.24. In the first case, it would be preferable to crystallize the enriched enantiomer to optical purity, e.g., methylphenidate. However, in the second case, a very stable racemic compound exists, giving rise to a high eutectic point. Here crystallization of enriched enantiomer mixture will only be successful at high ee. For example, verapamil hydrochloride requires that the ee be greater than 98%for crystallization to yield... 

One of the most widely used calcium channel blockers is verapamil. Verapamil hydrochloride was assayed from pharmaceutical preparations by ElGhany et al. [133]. The separations were performed on 200 x 100 mm and 100 x 100 mm silica gel 60 F254 plates using an ethyl acetate/methanol/water mobile phase and scanning the plates at 278 nm. The accuracy and precision data for the assay of spiked verapamil samples and the recovery data of verapamil from commercial preparations are shown in Tables 10.20 and 10.21. 

THE ACCURACY AND PRECISION DATA FOR THE ASSAY OF SPIKED VERAPAMIL HYDROCHLORIDE SAMPLES. REPRODUCED WITH PERMISSION FROM [133]... 

Goracinova, K. Klisarova, L. Simov, A. Fredro-Kumbaradzi, E. Petrusevska-Tozi, L. Characterization of fluid bed prepared granulates with verapamil hydrochloride as active substance. Acta. Pharm. 1996, 46, 147-153. 

G. Properties of the racemic species of verapamil hydrochloride and gallopamil hydrochloride. Int. J. Pharm. 1999,178, III-I20. 

Sipahigil O, Dortunc B. Preparation and in vitro evaluation of verapamil hydrochloride and ibuprofen containing carrageenan beads. Int ] Pharm 2001 228(1-2) 119-128. 

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