New Antihypertensiv Drugs Essay, Research Paper

The purpose of this report is two discuss the Pharmacodynamics, pharmacokinetics, proposed benefits, research method, results of research, and possible-nursing implications of newly approved drugs for the treatment of hypertension. These drugs include Atacand HCT and Diltiazem HCL. All newly approved drugs from the FDA are either new drugs or new formulations of older drugs. The information contained in this report was derived from various web pages and online search engines.

Pharmacokinetics: Atacand HCT (Candesartan celexetil)

Candesartan is quickly and completely bioactivated by hydrolysis during the absorption from the GI tract to a angiotensin II receptor antagonist (www.rxlist.com). Candesartan is excreted mainly unchanged in urine and feces through bile. Atacand’s other component is hydrochlorothiazide, which is a thiazide diuretic. Thiazide effect the renal tubular mechanisms of electrolyte reabsorption. This is done directly by increasing the excretion of sodium and chloride in equal amounts (www.centerwatch.com). Post administration Candesartan celexetil bioavailability was estimated at 15%, peak concentration was reached within 3-4 hours and inactive metabolites were not shown to accumulate upon daily dosing (www.rxlist.com). The distribution of Candesartan was reported at 0.13 l. per kilogram; in the shown to be highly bound to plasma proteins (*99%). Candesartan was not shown through laboratory testing of rats to cross the blood brain barrier, the drug was shown however through these studies to cross the placental barrier and is distributed in the fetus (www.rxlist.com).

Pharmacodynamics: Atacand HCT

Candesartan inhibit the effects of angiotensin II in a dose dependent fashion. After a once daily dosing of 8 mg Candesartan celexetil over a one week duration the drugs pressor effect was inhibited by approximately 90% at the peak, and by 50% 24 hours later (www.rxlist.com). In a 12 week study of diabetic type II patients (n=161) their where no changes in the level of HbA1C (www.rxlist.com).

Proposed benefits of drug: Atacand HCT

Atacand HCT (Candesartan celexetil-hydrochlorothiazide) was developed for patients who were unsuccessfully treated with single antihypertensive agents. The proposed benefit is elicited by the drugs action on angiotensin II receptor antagonists, the agent that causes vasoconstriction. Additionally the second ingredient hydrochlorothiazide a diuretic reduces blood pressure by improving the kidneys ability to eliminate salt and fluid from the body (www.centerwatch.com).

Research method: Atacand HCT

They were five double blind, placebo controlled trials for Candesartan celexetil hydrochlorothiazide, which we’re eight weeks to twelve weeks in duration. The combined study sample consisted of 3,037 hypertensive patients and dosage ranged from 2 to 32 mg Candesartan celexetil and from 6.25 to 25 mg hydrochlorothiazide administered once daily in several combinations (www.centerwatch.com).

Results of drug research: Atacand HCT

The antihypertensive effects of Atacand was similar in men and women in patients older and younger than 65 (www.rxlist.com). Atacand HCT or the combination (Candesartan celexetil and hydrochlorothiazide) resulted in placebo adjusted decreases in sitting systolic and diastolic blood pressures between 14-18/ 8-11 mmHg at doses of 16-12.5 mg and 32-for 12.5 mg (http://nursing.medscape.com).

Nursing implications: Atacand HCT

Monitor blood pressure and pulse frequently during dosage adjustment and periodically throughout therapy. Monitor intake and output ratios and daily weight (www.lexilcom). Monitor frequency of prescription refills to determine compliance (J. Deglin, A. Vallerand, 1999).

Nursing Diagnosis: Atacand HCT

Tissue perfusion, altered (indications)

Knowledge deficit, related to medication regimen

Noncompliance

Risk for injury, fall

Pharmacokinetics: Diltiazem HCL ORAL

80% of the oral dose is absorbed from the GI tract, only about 40% will reach systemic circulation due to an extensive first-pass effect (http://promini.medscape.com). Binding studies show diltiazem HCL is 70% to 80% bound to plasma proteins (www.medsafe.govt). One study showed an increase of 69% in individuals with impaired hepatic functioning or sclerosis of the liver (www.medsafe.govt).

Pharmacodynamics: Diltiazem HCL ORAL

Diltiazem HCL inhibits the influx of calcium ions during membrane de-polarization and is known as a calcium antagonist (www.medsafe.govt). diltiazem decreases the sinoatrial in the atrioventricular conduction in isolated tissues, and is known to have a negative iontropic effect (www.medsafe.govt). this causes a decrease in vascular resistance do to the relaxation of the vascular smooth muscle (www.rxlist.com). By inhibiting the contractile processes of the cardiac and vascular smooth muscle diltiazem dialates the main coronary and systemic arteries, decreasing myocardial contractility (http://promini.medscape.com).

Proposed benefits of drug: Diltiazem HCL ORAL

The proposed benefit of diltiazem HCL is to relieve and control angina, to reduce high blood pressure, and to correct heartbeat irregularities, in an easily administered once a day tablet.

Research method: Diltiazem HCL ORAL

The research method that was used was a double blind, parallel, dose-response study utilizing dosages the from 90 to 540 mg once daily (www.rxlist.com). Further all participants had their blood pressures measured while in the supine position (www.rxlist.com).

Results of drug research: Diltiazem HCL ORAL

In the double blind study of doses from 60 mg to 480 mg once daily participants the duration of time until the termination of exercise along the entire dosage range (www.rxlist.com). Important is the finding that in patients with sick sinus syndrome there was an elongation of the PR interval of up 50% (www.rxlist.com).

Nursing implications:Diltiazem HCL ORAL

Monitor blood pressure and pulse frequently during dosage adjustment and periodically throughout therapy. Monitor intake and output ratios and daily weight. Monitor frequency of prescription refills to determine compliance (J. Deglin, A. Vallerand, 1999).

Nursing Diagnosis: Diltiazem HCL ORAL

Tissue perfusion, altered (indications)

Knowledge deficit, related to medication regimen

Noncompliance

Risk for injury, fall