prepared by: dr rasol m hasan. anti- hypertensive drugs
TRANSCRIPT
Prepared by:
Dr Rasol M Hasan
Anti- HYPERTENSIVE
Drugs
Vasodilators
Examples:
ClonidineMethyldopa
HexamethoniumGuanithidine, reserpine, alpha
blockersAmyl nitrate
Hydralazine (oral)Minoxidil(parenteral)
NesiritideFenoldopam
Na nitroprussideDiazoxide
Calicium ch. BlockersACEI, Angio.recep.blockers
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Sympatholytics
CENTRALLY ACTING ALPHA2-AGONISTS
CLONIDINE,METHYLDOPA
• decreases the sympathetic response from brainstem to peripheral vessels• Stimulate alpha2 receptors: increase vagus activity, decrease cardiac output and decreases serum epinephrine, norepinephrine & renin release• results into reduced peripheral vascular resistance
Side effects: - drowsiness, dry mouth and nasal
mucosa, dizziness, orthostatic hypotension impotence , sodium and fluid retention.
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
ACE Inhibitors
- Angiotensin Antagonists (Angiotensin-Converting Enzyme [ACE] Inhibitors)
Action: - Inhibits ACE which in turn
inhibits formation of angiotensin II (vasoconstrictor) and blocks the release of aldosterone
Side effects: - Constant irritation cough;
Nausea; Vomiting; Diarrhea; Fatigue; Hyperkalemia; Tachycardia
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
ACE Inhibitors
Indication:- Hypertension (control blood
pressure); Prevention of cardiovascular disorders; Preventing kidney damage in people with hypertension or diabetes; Congestive heart failure (CHF); Left ventricular dysfunction Contraindication:
- Pregnancy (Lowers placental blood flow); Hypotension
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Vasodilators
- Direct Acting Arteriolar Vasodilators eg hydralazine old vasodilator mainly arteriolar dilator
Action: - act as blood vessel dilators- relaxes vascular smooth muscles
which decrease peripheral vascular resistance and therefore reduces blood pressure
Uses of Vasodilators: Systemic and Pulmonary Hypertension Heart Failure Angina
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
VasodilatorsSide Effects: CNS: Headache; Peripheral neuropathy; Dizziness CVS: Palpitation; Flushing; Reflex tachycardia; Angina; Ischemic arrhythmias GIT: Nausea; Anorexia Skin: Sweating; Lupus erythematosus like syndrome characterized by: Myalgia, Arthralgia, Skin rashes, Fever Renal: Edema hypotensionECG changes Drowsiness Dry mouth Fatigue
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Vasodilators
Contraindications: ischemic heart disease Lupus erythematosus acute MIDMtachycardia thyrotoxicosis
Precautions:- caution should be used in
uncompensated heart disease or peptic ulcer disease
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Vasodilators
Pharmacokinetics: - onset, peak, and duration vary
widely among products. Most products are metabolized in the liver and excreted in urine
Interactions:- varies widely among products
Example of PHARMACOKINETICS OF ` HYDRALAZINE
Oral vasodilator but can be given I/VRapidly metabolized by the liver during first pass bioavailability is
low averaging 25%variable among individuals.
Well absorbed.
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Ca Channel Blockers
3 CHEMICAL CLASSES: Phenylalkylamines – Verapamil (Calan, Isoptin, Verelan) Benzothiazepines – Diltiazem (C ardizem, Dilacor, Tiazac) Dihydropyridines – Amlodipine (Norvasc), Felodipine (Plendil), Nicardipine (Cardene), Nifedipine (Adalat, Procardia)
Mechanism of action: Prevents calcium from entering the
excitation-contraction process therefore, prevents muscle contraction and, instead, promotes relaxation of the smooth muscles that surrounds the coronary arteries and causes them to dilate.
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Ca Channel Blockers
Indications: Angina Hypertension Supraventricular tachycardia For short-term management of atrial fibrillation and flutter, migraine Headaches.
Contraindications: Drug allergy Acute MI Second- or third-degree atrioventricular block Hypotension
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Ca Channel Blockers
Adverse Effects:HypotensionPalpitationsTachycardia or bradycardiaNauseaConstipationDyspneaFlushingPeripheral edema
Common Drug Interactions• Beta-Blockers• Digoxin – possible increased digoxin level• H2 blockers – elevated levels of Calcium channel blockers• Grapefruit can reduce the metabolism of Ca channel blockers
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Sympatholytics
5 groups of drugs:1. Beta-adrenergic blockers2. Centrally acting alpha2-agonists3. Alpha-adrenergic blockers4. Adrenergic neuron blockers
(Peripherally acting sympatholytics)5. Alpha1 and Beta1 adrenergic blockers
Sympatholytics:[anti-adrenergic]- reduces the physiological effects caused
by stimulation of the sympathetic nervous system
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Sympatholytics
BETA-ADRENERGIC BLOCKERS (Beta-blockers)
Step 1- antihypertensive drugsStep 2 - in combination with diuretics
- also used as antianginals and antidysrhythmics- reduces cardiac output by blocking the SympathNS response thus decreasing basal sympathetic tone- continued use: reduces vascular resistance and lowers BP- reduces HR, contractility and renin release- can cross the placental barrier and enter breast milk
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Sympatholytics
BETA-ADRENERGIC BLOCKERS (Beta-blockers)
Types:1.Nonselective
• inhibits beta1 (heart) and beta2
(bronchial) receptors• decrease BP secondary to decrease and
bronchoconstriction occurs2.Cardioselective
• act mainly on beta1; bronchoconstriction less likely to occur
Oral Beta-blockers
• Onset of action: 30 mins. or less• Duration: 6 to 12 hours
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Sympatholytics
BETA-ADRENERGIC BLOCKERS (Beta-blockers)
IV Beta-blockers• Onset of action: immediate• Peak: 20 mins.• Duration: 4 to 10 hours
Side Effects: - dizziness, weakness, wheezes,
shortness of breath, Adverse Reactions:
- Bradycardia, bronchospasms, markedly decrease BP
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Sympatholytics
BETA-ADRENERGIC BLOCKERS (Beta-blockers)
Precaution: Should not be used by clients with 2nd- or 3rd-degree AV block or sinus bradycardia. Noncardioselective beta-blocker should not be given in patients with COPD Inform patients that herbs can interfere with beta-blockers
Example of drugs:PropanololMetoprololAcebutololAtenolol
Bisoprolol
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Sympatholytics
CENTRALLY ACTING ALPHA2-AGONISTS
Adverse reactions:- Peripheral edema
Example of drugs: Clonidine Methyldopa
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Sympatholytics
ALPHA-ADRENERGIC BLOCKERS
• blocks alpha-adrenergic receptors which results in vasodilation and decrease BP• maintains renal blood flow rate• useful in clients with lipid abnormalities• safe for diabetic patients because it does not affect glucose metabolism
Side effects: - dizziness, headache, vomiting,
nausea, drowsiness, and nasal congestion, dry mouth
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Sympatholytics
ALPHA-ADRENERGIC BLOCKERS
Adverse reactions: - orthostatic hypotension
Example of drugs: Prazosin Terazosin Doxazosin PhentolamineSympatholyti
cs
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Sympatholytics
ADRENERGIC NEURON BLOCKERS
• blocks norepinephrine release, thus lowers BP• decreases cardiac output and peripheral vascular resistance
Side effects: - dizziness, weakness, nausea,
drowsiness
Adverse reactions: - Orthostatic hypotension, peripheral
edema
Example of drugs:Reserpine Guanethidine
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
SympatholyticsALPHA1 AND BETA1
ADRENERGIC BLOCKERS
•blocking alpha1 receptor results in dilation of the arterioles and veins.• decreases BP and moderately decreased PR
Side effects: -dizziness, weakness, nausea and
vomiting, nervousness, dry mouth and fatigue
Adverse reactions: - Orthostatic hypotension
Example of drugs:Labetalol
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Angiotensin Receptor Blockers
Indications: • Hypertension, alone or when in combination with other anti-hypertensive drugs.• Nephropathy in type II DM• Heart failure in those intolerant to ACE inhibitors• Reduce risk of stroke
Contraindications and Special Considerations• Drug Allergy• Pregnancy and lactation• Elderly patients• Patients with renal dysfunction
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Angiotensin Receptor Blockers
Examples: Losartan (Cozaar)
Eprosartan (Teveten) Valsartan (Diovan) Irbesartan (Avapo)
Candesartan (Atacand) Olmesartan (Benicar) Telmisartan (Micardis)
Sympatholytics
ACE Inhibitors
Vasodilators
Diuretics
Ca Channel Blockers
Angiotensin Receptor Blockers
Angiotensin Receptor Blockers
Serious Side Effects: Altered Liver Function Kidney Impairment Hyperkalemia Orthostatic hypotension
Toxicity and ManagementOverdose may manifest:• Hypotension• Tachycardia, bradycardia occurs less often treatment is symptomatic and supportive. It includes the administration of IVFs to expand the blood volume
Drug to Drug Interaction- can interact with cimetidine, Phenobarbital, and rifampin.
Sympatholytics