Hypotension first-dose

Initially 1 mg bid-tid increase 5-15 mg bid-tid orthostatic hypotension first dose at bedtime caution in coronary artery disease. 

Postural hypotension, first-dose effect, and rebound phenomenon are not commonly seen. 

Excessive hypotension ("first-dose syncope") mayoccurin patients with CHFand in those who are severely salt or volume depleted. 

Excessive hypotension ("first-dose syncope") mayoccurinpatientswithCHFand in... 

Excessive hypotension ( first-dose syncope) may occur in those with CHF, severely salt/volume depleted... 

However, it is also the major reason for the adverse side effects of ACE inhibitors, namely cough and angio-oedema. Another observed side effect, first-dose orthostatic hypotension, is probably due to both angiotensin inhibition and kinin potentiation. 

Generally, arblockers are considered as second-line agents to be added on to most other agents when hypertension is not adequately controlled. They may have a specific role in the antihypertensive regimen for elderly males with prostatism however, their use is often curtailed by complaints of syncope, dizziness, or palpitations following the first dose and orthostatic hypotension with chronic use. The roles of doxazosin, terazosin, and prazosin in the management of patients with hypertension are limited due to the paucity of outcome data and the absence of a unique role for special populations or compelling indications from JNC 7. 

Angiotensi n-converti ng Hypotension, cough (with ACE inhibitors), BP every 2 hours x 3 for first dose, then every shift during oral... 

Sargramostim Neutrophil, 250 mcg/m2 per day First-dose effect (hypotension, flushing) Indicated for use following... 

Prazosin constipation First-dose orthostatic hypotension... 

A potentially severe side effect is a first-dose phenomenon characterized by orthostatic hypotension accompanied by transient dizziness or faintness, palpitations, and even syncope within 1 to 3 hours of the first dose or after later dosage increases. These episodes can be obviated by having the patient take the first dose, and subsequent first increased doses, at bedtime. Occasionally, orthostatic dizziness persists with chronic administration. 

Patients should be slowly titrated to a maintenance dose and should take these drugs at bedtime to minimize orthostatic hypotension and first-dose syncope with terazosin and doxazosin. Sample titration schedules for terazosin include ... 

Hypertension 1-10 mg qhs first-dose hypotension peripheral edema caution In atherosclerotic disease. 

Alfuzosin is a selective alpha-blocker, which relaxes smooth muscle, thereby increasing urinary flow rate. Because of its alpha-blockade effect, alfuzosin tends to lower the blood pressure and the first dose of the drug may lead to a hypotensive effect. 

Alpha-blockers tend to cause vasodilation leading to hypotension especially after the first dose. Subsequently patients on alpha-blockers are advised to take the first dose at night before retiring to bed. Alpha-blockers also tend to cause drowsiness so patients are advised to be careful when driving. 

Q60 When a patient who is receiving atenolol is started on terazosin, there is an increased risk of first-dose hypotension. Terazosin is an alpha-adrenoceptor agonist which causes vasodilatation. 

Terazosin is an alpha-adrenoreceptor blocker that causes vasodilation and is used in the management of hypertension and benign prostatic hypertrophy. Beta-blockers and alpha-blockers can interact to induce hypotension since both act to reduce the blood pressure. Patients already on beta-blockers and who are started on alpha-blockers such as terazosin should be advised to take the terazosin dose at night to reduce the implications (falls) of first-dose hypotension. 

Terminate IV therapy if persistent conduction disturbances or hypotension develop. As soon as the patient s basic cardiac rhythm appears to be stabilized, oral antiarrhythmic maintenance therapy is preferable (if indicated and possible). A period of approximately 3 to 4 hours (one half-life for renal elimination, ordinarily) should elapse after the last IV dose before administering the first dose of oral procainamide. 

Acute Ml - In hemodynamically stable patients within 24 hours of the onset of symptoms of acute Ml, the first dose is 5 mg, followed by 5 mg after 24 hours, 10 mg after 48 hours and then 10 mg once daily. Continue dosing for 6 weeks. Patients with a low systolic BP (120 mm Hg or less) when treatment is started or during the first 3 days after the infarct should be given a lower 2.5 mg dose. If hypotension occurs (systolic BP 100 mm Hg or less), a daily maintenance dose of 5 mg may be given with temporary reductions to 2.5 mg if needed. If prolonged hypotension occurs (systolic BP less than 90 mm Hg for more than 1 hour), withdraw lisinopril. 

Adverse reactions Postural hypotension, tachycardia, miosis, nasal stuffiness, failure of ejaculation Same as phenoxybenzamine and in addition gastrointestinal disturbances Some postural hypotension, especially with the first dose less of a problem overall than with phenoxybenzamine or phentolamine... 

Hypotension or postural hypotension may occur with first doses... 

First-dose syncope (hypotension with sudden ioss of consciousness) may occur 30 to 90 min foiiowing initiai dose of 2 mg or greaf er, a f oo-rapid increase in dosage, or addif ion of anof her anf ihyperfensive agenf f o f herapy. First-dose syncope may be preceded by tachycardia (puise rate of i20-i60 beafs/minute). 

Somnolence, hypotension, dizziness, fainting (commonly occurring after first dose, occasionally after subsequent doses, and rarely with oral form)... 

The answer is e. (Katzung, pp 141, 168.) Prazosin blocks tti-adrenergic receptors in arterioles, thereby decreasing peripheral resistance and leading to a decrease in blood pressure. Orthostatic hypotension can occur, particularly after a first dose. 

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