Water Lisinopril

Undesired effects. The magnitude of the antihypertensive effect of ACE inhibitors depends on the functional state of the RAA system. When the latter has been activated by loss of electrolytes and water (resulting from treatment with diuretic drugs), cardiac failure, or renal arterial stenosis, administration of ACE inhibitors may initially cause an excessive fall in blood pressure. In renal arterial stenosis, the RAA system may be needed for maintaining renal function and ACE inhibitors may precipitate renal failure. Dry cough is a fairly frequent side effect, possibly caused by reduced inactivation of kinins in the bronchial mucosa. Rarely, disturbances of taste sensation, exanthema, neutropenia, proteinuria, and angioneurotic edema may occur. In most cases, ACE inhibitors are well tolerated and effective. Newer analogues include lisinopril, perindo-pril, ramipril, quinapril, fosinopril, benazepril, cilazapril, and trandolapril. 

Lisinopril/hydrochlorothiazide is antihypertensive combination. Lisinopril competitively inhibits angiotensin I-converting enzyme and prevents angiotensin I conversion to angiotensin n, reversing the potassium loss associated with the diuretic. Hydrochlorothiazide increases chloride, sodium, and water excretion by interfering with transport of sodium ions across renal tubular epithehum. They are indicated in the treatment of hypertension. 

Lisinoprii has been prepared by the scheme outlined in Figure 1 (7,8). The dipeptide, Ng-trifluoroacetyl-L-lysyl-L-proline (D is subjected to reductive alkyiation with ethyl 2-oxo-4-phenylbutanoate over Raney Nickel via a Schiff base to yield a diastereomeric mixture 4 (SSS and RSS). Hydrolysis of the N -trifluoroacetyl moiety and saponification of the ethyl ester followed by crystallization in ethanol/water and final recrystallization in water yield lisinopril (SSS, 5) of greater than 98% purity in about 65% yield (based on In addition to this synthetic route, others have also been described in the literature (9-12). 

The thermogravimetric analysis (TGA) curve of lisinopril shown in Figure 10 depicts three inflections corresponding to the loss of free water and the first and second moles of water of hydration. The excess unbound water was 0.6% over the theory of 8.2% for the dihydrate indicating lisinopril is somewhat hygroscopic. 

Upon dissolution of lisinopril in methanol, changes in X-ray diffraction patterns indicative of loss of water of hydration were observed. The solubility value obtained becomes dependent upon the water content of the solution. 

Electrolyte balance Hypernatremia has been reported in a 44-year-old woman with normal renal function who was given too much sodium polystyrene sulfonate she was also taking furosemide, spironolactone, and lisinopril [39 ]. The authors attributed this to net intestinal water loss because of profuse osmotic diarrhea. 

Due to the absence of water, which catalyses many chemical reactions, chemical incompatibilities rarely occur in dry dosage forms. One exception is the incompatibility of the excipient lactose with primary amines, such as amphetamine and lisinopril. The rate of the reaction (Maillard reaction) is slow in absence of water, but may lead to yellow discolouration during storage [25]. 

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