Pharmacology Ch. 43 AntiHTN

Indications: treatment of HTN, CHF, diabetic neuropathy, left ventricular dysfunction after and MI

Actions: block the conversion of angiotensin I to angiotensin II in the lungs. This stops that phase of the renin-angiotensin system before vasoconstriction can occur or aldosterone can be released. Small increase in serum K+ levels along with sodium and fluid loss

Contraindications/cautions: allergy, impaired renal function, pregnancy and lactation, caution should be used in CHF and salt/volume depletion.

Drug to Drug: allopurinol

Adverse Effects: tachycardia, MI, rash, pruritis, gastric irritation, aphthous ulcers, peptic ulcers, dysgeusia, proteinuria, bone marrow supression, cough

*patient should take on empty stomach, 1 hour before or 2 hours after meals
*associated with fatal pancytopenia and MI

Indications: alone or as part of combination therapy for the treatment of HTN; treatment of diabetic nephropathy with an elevated serum creatinine and proteinuria in patients with type II diabetes and hypertension

Actions: selectively bind the angiotensin II receptors in blood vessels to prevent vasoconstriction and in the adrenal cortex to prevent the release of aldosterone that is caused by reaction of these receptors with angiotensin II. This leads to decrease in BP caused by a decrease in total peripheral resistance and blood volume.

Excreted in feces and urine

Contraindications and Cautions: allergy, pregnancy, and lactation. caution in hepatic/renal dysfunction, and hypovolemia

Drug to drug: serum levels and loss of effectiveness when taken with phenobarbital

Adverse Reactions: dizziness, headache, diarrhea, abdominal pain, symptoms of upper respiratory tract infection, cough, back pain, fever, muscle weakness, and hypotension

Indications: treatment of HTN

Actions: inhibit the movement of calcium ions across the membranes of myocardial and arterial muscle cells, altering the action potential and blocking muscle cell contraction. this effect depresses myocardial contractility, slows cardiac impulse formation in the conductive tissue and relaxes and dilates arteries, causing a fall in BP and decrease in venous return

Contraindications/Cautions: allergy, heart block or sick sinus syndrome, renal or hepatic dysfunction and pregnancy and lactation

Drug/Drug: increase serum levels and toxicity of cyclosporine if taken with diltiaxem

Adverse: relate to effects on cardiac output and smooth muscle; dizziness, light headedness, headache, fatigue, nausea, hepatic injury, hypotension, bradycardia, peripheral edema, heart block, skin flushing

Indications: Hypertensive crisis, severe hypertension that is unresponsive to other treatment, maintenance of controlled hypotension during anesthesia, acute CHF

Actions: act directly on the smooth vascular smooth muscle to cause relaxation, leading to vasodilation and drop in BP

Contraindications/Cautions: allergy, pregnancy, lactation, condition with sudden fall of BP, caution with PVD, CAD, CHF, tachycardia

Adverse: related to changes in BP; dizziness, anxiety, headache, reflex tachycardia, CHF, chest pain, edema, skin rash, lesions, abnormal hair growth with minoxidil, nausea, vomiting, cyanide toxicity (dyspnea, headache, vomiting, ataxia, loss of consciousness, absent reflexes, dilated pupils, distant heart sound, shallow breathing) may occur with nitroprusside, which is metabolized to cyanide and also suppresses iodine uptake, which can lead to hypothyroidism

indications: treatment of orthostatic hypotension when no other treatments have been effective.

Actions: activates alpha-receptors in arteries and veins to produce an increase in vascular tone and increase in BP

Contraindications/cautions: presence of supine hypertension, CAD, pheochromocytoma, acute renal disease, urinary retention, and thyrotoxicosis; Caution with pregnancy and lactation, visula problems and renal and hepatic impairment

Drug to drug: risk of increased effects/toxicity with cardiac glycosides, beta blockers, alpha andrenergic blockers, and corticosteroids

Adverse: related to stimulation of alpha receptors and include piloerection, chills, rash, hypertension and bradycardia, dizziness, vision changes, vertigo and headache, and problems with urination