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It is also well absorbed from the gastrointestinal tract, but as it undergoes extensive first-pass metabolism in the liver, its bioavailability is reduced. It is also indicated in congestive heart failure and may play a role in the treatment of myocardial infarction. It is used for angina pectoris, usually in oral doses of 10 to 40 mg three or four times a day.

It is stored in tightly closed containers, sealed to exclude microorganisms and stored in a dry place. Protamine sulfate is used to neutralize the anticoagulant effect of heparin in the treatment of bleeding resulting from severe overdose of heparin.

Dicoumarol (30) or Dicouman and other related derivatives

Anti-hypertensive Agents Introduction

Blood pressure is a measurement of the pressure of blood on the walls of blood vessels. Persistent high blood pressure causes unnecessary stress on the heart, blood vessels and other organs. Blood pressure is a measure of the force of the blood pushing against the walls of the arteries (ie the blood vessels that carry blood from the heart to the rest of the body).

Systolic blood pressure (SBP): When the heart contracts to pump blood out, pressure is highest. The measurement of an individual's blood pressure is always expressed as systolic pressure over diastolic pressure.

General Classification of Hypertension

According to the WHO, systolic and diastolic blood pressure in a normal adult is equal to or below 140 mm Hg and 90 mm Hg.

Other kinds of Hypertension

  • α - Adrenergic Antagonist
  • Directly Acting Vasodilators

About 2,00,000 deaths per year in the world occur due to acute pulmonary embolism (a common cause of sudden onset pulmonary HTN). Renal parenchymal hypertension: It is associated with renal parenchymal disease and the most common form of secondary hypertension; 5% of all hypertensive patients have underlying kidney disease. Examples include the use of drugs such as alcohol or medications such as corticosteroids, cyclosporine, estrogen (including birth control pills), nasal decongestants, corticotropin or other hormones, sympathomimetic medications, which are found in many over-the-counter cough/cold medications. medicine and medication for asthma or especially when the cough/cold medicine is taken by a person who is also taking tranylcypromine or tricyclic antidepressants. It can also result from discontinuing the use of antihypertensive medications such as clonidine.

The generic names and trade names of the common antihypertensives and their dosage, frequency of administration, duration of action are summarized in the table for the treatment. Prazosin hydrochloride is used to treat all degrees of hypertension, usually as a second-step agent along with a diuretic or other antihypertensive agent. Propranolol is used to treat hypertension, to improve exercise tolerance in patients with angina pectoris, and has been given to prevent reinfarction in patients who have had an acute myocardial infarction.

The metabolites are excreted in the urine together with only small amounts of unchanged labetalol. It is extensively metabolized and excreted in the urine as unchanged drug and O-sulfate conjugate. Methyldopa is used to treat moderate to severe hypertension along with a diuretic.

In psychiatric conditions, 1 to 5 mg daily in divided doses is given orally, and in the treatment of hypertension, the dose is 0.5 mg daily. Guanethidine sulfate is used to treat hypertension when other drugs have proven inadequate. It is slowly excreted by the kidneys in unchanged form and has a relatively long duration of action.

Diuretics

Cardiac Glycosides Introduction

The steroid aglycone of the glycosides is responsible for cardiac activity and sugars provide favorable solubility and distribution, thus influencing its potency and duration of action. Sugars: The hydroxyl group at C-3 of the aglycone portion is usually conjugated to a monosaccharide or a polysaccharide with β-1,4-glucosidic bonds. The presence of an O-acetyl group on a sugar has a major influence on the lipophilicity and pharmacokinetics of the entire glycoside.

Cardiac glycosides are the cardiotonic substances that increase the contractile force of the heart and exert important actions on the heart's excitability, automation, conduction rate and. The aglycone portion of the cardiac glycosides is a steroid core with a unique series of fused rings, making it easy to distinguish these agents from the other steroids. The size and degree of unsaturation of the lactone ring varies depending on the source of the glycoside. i).

In digitalis glycosides: A - B and C - D ring annelation is cis (Z), 3 -OH is axial and all these steroids carry a 14β-OH group. Coplanar compounds with marginal activity: where side chains instead of a ring have even higher activity. v) The activity of a compound depends to a great extent on the position of the 23rd carbonyl oxygen, which is held quite rigidly by the D-ring and the double bond. vi) Removal of the sugar portion allows epimerization of the 3β-OH group, with decreased activity and increased toxicity due to changes in polarity. The size and degree of unsaturation of the lactone ring varies with the source of the glycoside.

It contains the aglycone digoxigenin and. the sugar part consists of three D-digitoxose molecules. It is the most potent digitalis glycoside and is the most cumulative in action. Replacement of the sugar moieties with nitrogen-containing side chains gives potent digitalis analogs, e.g.

Vasodilators

Hydralazine is a direct vascular smooth muscle relaxant for the treatment of moderate to severe hypertension. Causes reflex tachycardia and fluid retention; therefore, it should always be given in combination with a β-adrenergic receptor blocker and a diuretic. Nitric oxide can be generated by hydralazine; therefore, its action is similar in mechanism to sodium nitroprusside and organic nitrites.

Minoxidil (91), a piperidino-pyrimidine derivative directly relaxes arterial smooth muscle and is indicated for patients with severe hypertension unresponsive to other drugs. It is biotransformed to an active metabolite, minoxidil N→O sulfate, which releases vascular smooth muscle and increases the permeability of the cell membrane to K+, resulting hyperpolarization. Diazoxide ( 90 ) hyperpolarizes arterial smooth muscle cells by activating ATP-sensitive K + channels; it causes relaxation of the vascular smooth muscle.

Sodium nitroprusside (Nipride): Nitroprusside (137) is used for short-term and rapid lowering of blood pressure in hypertensive emergencies. In the vascular endothelium it forms an active nitrosothiol with glutathione that increases cyclic GMPI, thereby causing vasodilation. Hydralazine hydrochloride is used to treat moderate h, severe hypertension usually in conjunction with a beta-blocker and a thiazide diuretic.

The oral dose is 10 mg four times a day, gradually increasing up to 50 mg four times a day. Can be given by slow intravenous injection or intravenous infusion for hypertensive emergencies; dose range is 20 to 40 mg, repeated as needed. The parenteral dose is 1 to 3 mg per kg of body weight within 30 seconds, up to a maximum of 150 mg and repeated after 5 to 15 minutes, if required.

Anti-arrhythmic Agents Introduction

Antiarrhythmic Drugs: drugs are generally local anesthetics acting on nerve and myocardial membranes to slow conduction by inhibiting phase 0 of the action

Drugs: β-Receptor antagonists (See antihypertensive agents) Class II antiarrhythmic drugs are, β-adretiergic receptor blocking agents, which blocks

At higher doses, these drugs may also exhibit anesthetic properties, causing decreased excitability, decreased conduction velocity, and a prolonged effective refractory period. In normal therapeutic situations, the β-blocking effects are more important than any local anesthetic effect that these drugs may have. It is useful in ventricular arrhythmias due to increased adrenergic stimulation (from emotional stress, exercise).

Esmolol is particularly useful for the treatment of supraventricular tachycardia due to its very short action (half-life 9 minutes).

Antiarrhythmic Drugs

CH2CH3 CH2CH3 Amiodarone (173) . Amiodarone Hydrochloride: 2-Butyl-3-benzofuranyl)[4-(diethylamino)ethoxy]-3,5-diiodophenyl]methenone (173) is an iodinated benzofuran derivative. Its use is reserved for the treatment of life-threatening ventricular arrhythmias that are refractory to other treatments. It is also possible that its antiarrhythmic effects are mediated in part by selectively inhibiting the action of thyroxine on the heart.

Iodine can be replaced by bromine and methyl and the benzofuran ring by the benzothiophene ring without loss of activity. Substitution of indolizine for the benzofuran ring in amiodarone gave butoprozine with higher antiarrhythmic activity.

Antiarrhythmic Drugs: Calcium-channel Blockers

Antiarrhythmic Drugs: Anion antagonists

  • Hypoglycemic Agents Introduction
  • OCH 3
  • CH 2 SO 2 NHCONH
  • CH 2 OCH 3

Quinidine can be used as an alternative to quinine in the treatment of malaria when quinine is not immediately available. In the treatment of atrial fibrillation, a 0.2 to 0.4 g dose is given every two to four hours to a total dose of 3 g daily. They are involved in the transport of endogenous lipid from liver to the plasma. iii).

As a result of the further action of lipoprotein lipase on IDL in the circulation, most of the remaining triglyceride content of IDL is digested, leading to the loss of apoproteins C and E from their structure. In the treatment of familial hypercholesterolemia, a combination of cholestyramine and nicotinic acid usually gives better results. Clofibrate is used in conjunction with dietary modification in the treatment of type III hyperlipoproteinemia and severe hypertriglyceridemia.

It is mainly characterized by an unusually high level of sugar in the blood (hyperglycemia) and the presence of sugar in the urine (glucosuria). The large urine volume is due to the large amounts of glucose and urea in the urine (osmotic diuresis). Insulin is synthesized by cells of the islets of Langerhans of the pancreas in the form of proinsulin.

Bovine insulin has 2 amino acids in the middle of chain A and one at the end of chain B that are different from human insulin. Insulin occurs as a hexamer containing two zinc atoms and in the system (in the blood) dissociates into monomers is the most likely biologically active form of insulin. Thus, there is almost complete homology between human insulin and porcine insulin in the amino acid sequence.

It can be concluded that chemical modifications in the insulin structure fail to enhance hormone activity. The therapeutic importance of zinc and chromium in the treatment of diabetes has recently been reviewed.

Table 4: Insulin dependent versus non-insulin dependent forms of diabetes mellitus
Table 4: Insulin dependent versus non-insulin dependent forms of diabetes mellitus

Figure

Fig. Conformation of the C 3  and C 5 , esters of nifedipine (Ar = 2-nitrophenyl).  The C 3 ,  carbonyl is synplanar to the C 2 -C 3  bond, and the C 5  carbonyl antiperiplanar to the C 5 -C 6
Table 4: Insulin dependent versus non-insulin dependent forms of diabetes mellitus

References

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