Tolerance antihypertensives

III.c.6.2. Resistant hypertension. Hypertension should be considered resistant if the BP cannot be reduced to below 140/90 mmHg in patients who adhere to a triple-drug regimen that includes a diuretic, with all three drugs in near maximal doses. For older patients with isolated SBP, resistance is defined as failure of an adequate triple-drug regimen to reduce SBP below 160 mmHg. The various causes of true resistance are listed in Table 9. One of the most common causes is volume overload as a result of inadequate diuretic therapy. Patients who have resistant hypertension or who are unable to tolerate antihypertensive therapy may benefit from referral to a hypertension specialist. 

When angina occurs more frequently than once a day, chronic prophylactic therapy should be instituted. 8-Blockers may be preferable because of less frequent dosing and other desirable properties (e.g., potential cardioprotective effects, antiarrhythmic effects, lack of tolerance, antihypertensive efficacy). The appropriate dose should be determined by the goals outlined for HR and DP. An agent should be selected that is well tolerated by individual patients at a reasonable cost. Patients most likely to respond well to 8-blockade are those with a high resting HR and those with a relatively fixed anginal threshold (i.e., their symptoms appear at the same level of exercise or workload on a consistent basis). 

Finally, drug treatment in the elderly is of great importance and warrants special attention with regard to safety and tolerability, since systolic blood pressure is recognized as an important target for treatment, particularly in older persons. The benefits of antihypertensive treatment in the elderly and in patients with isolated systolic hypertension are greater than in younger persons. 

Antihypertensive therapy should be initiated in diabetic or nondiabetic CKD patients with an angiotensin-converting enzyme inhibitor (ACEI) or an angiotensin II receptor blocker. Nondihydropyridine calcium channel blockers are generally used as second-line antiproteinuric drugs when ACEIs or angiotensin II receptor blockers are not tolerated. 

Tamsulosin is a good choice for patients who cannot tolerate hypotension have severe coronary artery disease, volume depletion, cardiac arrhythmias, severe orthostasis, or liver failure or are taking multiple antihypertensives. Tamsulosin is also suitable for patients who want to avoid the delay of dose titration. 

Undesired effects. The magnitude of the antihypertensive effect of ACE inhibitors depends on the functional state of the RAA system. When the latter has been activated by loss of electrolytes and water (resulting from treatment with diuretic drugs), cardiac failure, or renal arterial stenosis, administration of ACE inhibitors may initially cause an excessive fall in blood pressure. In renal arterial stenosis, the RAA system may be needed for maintaining renal function and ACE inhibitors may precipitate renal failure. Dry cough is a fairly frequent side effect, possibly caused by reduced inactivation of kinins in the bronchial mucosa. Rarely, disturbances of taste sensation, exanthema, neutropenia, proteinuria, and angioneurotic edema may occur. In most cases, ACE inhibitors are well tolerated and effective. Newer analogues include lisinopril, perindo-pril, ramipril, quinapril, fosinopril, benazepril, cilazapril, and trandolapril. 

PENBUTOLOL SULFATE Usual starting and maintenance dose is 20 mg once daily. Doses of 40 to 80 mg have been well tolerated but have not shown greater antihypertensive effect. A dose of 10 mg also lowers blood pressure, but the full effect is not seen for 4 to 6 weeks. 

Because of their relative - selectivity, low doses of metoprolol, acebutolol, bisoprolol, and atenolol may be used with caution in patients with bronchospastic disease who do not respond to, or cannot tolerate, other antihypertensive treatment. Bradycardia Metoprolol produces a decrease in sinus heart rate in most patients this decrease is greatest among patients with high initial heart rates and least among patients with low initial heart rates. 

Bronchospasm, nonallergic (eg, chronic bronchitis, emphysema) In general, do not give -blockers to patients with bronchospastic disease. Flowever, carvedilol may be used with caution in patients who do not respond to, or cannot tolerate, other antihypertensive agents. If carvedilol is used, it is prudent to use the smallest effective dose so that inhibition of endogenous or exogenous -agonists is minimized. 

Isosorbide Dinitrate Hydralazine (BiDil) [Antianginal, Antihypertensive/Vasodilator, Nitrate] Uses HF in African Amer-icans improve survival functional status, prolong time between hospitalizations Action Relaxes vascular smooth muscle peripheral vasodilator Dose Initially 1 tab tid PO (if not tol ated reduce to 1/2 tab tid), titrate >3-5 d as tolerated Max 2 tabs tid Caution [C, /-] recent MI, syncope, hypovolemia, hypotension, hep impair Contra For children, concomitant use w/ PDE5 inhibitors (sildenafil) Disp Tabs SE HA, dizziness, orthostatic hypotension, sinusitis, GI distress, tach, paresthesia, amblyopia Interactions t Risk of severe hypotension W/ antihypertensives, ASA, CCBs, MAOIs, phenothiazides, sildenafil, tadalafil, vardenafil, EtOH X pressor response Wf i -1- effects W7 NSAIDs EMS Use ASA, antihypertensives and CCBs w/ caution, may t hypotension concurrent Viagra-type drug use can lead to profound hypotension concurrent EtOH use can t effects OD May cause N/V, profound hypotension, skin flushing, HA from ICP, bradycardia, confusion, and circulatory collapse activated charcoal may be effective, epi use is contraindicated... 

Selective a i-adrenoceptor antagonists are among the few antihypertensive agents that moderately improve the plasma lipid profile, glucose tolerance... 

Clonidine has been put forward for many years as the prototype of selective agonists of central o 2-adrenoceptor agonists. More recently it has been shown to be a mixed agonist of both 2- and 11-receptors in the central nervous system. It is an effective antihypertensive which has been used on a large scale for several decades. Its use has greatly declined in recent years because of its poor tolerability when compared with more modern antihypertensives. Sedation, dry mouth and sexual impotence are the most obvious side-effects. 

Prazosin may be particularly useful when patients caimot tolerate other classes of antihypertensive drugs or when blood pressure is not well controlled by other drugs. Since prazosin does not significantly influence blood uric acid or glucose levels, it can be used in hy-... 

The reduction in plasma volume produced by p-blockers contrasts with the increased volume seen with other types of antihypertensives. Tolerance to the antihypertensive actions of p-blockers therefore is less of a problem than with the vasodilating drugs. An additional difference from the vasodilators is that plasma renin activity is reduced, rather than increased, by propranolol (Inderal). Orthostatic hypotension does not occur with p-blockers. 

The p-blockers are quite popular antihypertensive drugs. They are well tolerated, and serious side effects are seldom observed. When used alone over several weeks, p-blockers produce a signihcant reduction in blood pressure in approximately 30% of patients with mild to moderate hypertension. Thus, -blockers can be employed as a first step in the management of high blood pressure. However, they are often used in conjunction with a diuretic when therapy with a single agent is not satisfactory. The combination of a p-blocker, thiazide diuretic, and vasodilator provides signihcant control of moderate to severe hypertension in approximately 80% of patients. 

The chief use of reserpine is in the treatment of mild to moderate hypertension. As with other sympathetic depressant drugs, tolerance to the antihypertensive effects of reserpine can occur, owing to a compensatory increase in blood volume that frequently accompanies decreased peripheral vascular resistance. Reserpine, therefore, should be used in conjunction with a diuretic. 

Psychoeducation of the patient and family is required to avoid the development of hopelessness in both the patient and family, and the clinician. Comparing these strategies with other treatments of medical disorders can be useful to help patients and their families understand the medication plan and to improve compliance with and tolerance of treatment. In this instance the example of hypertension is appropriate diuretics may be used alone, or combined with other antihypertensives in different trials, according to response. 

Pindolol. The antihypertensive beta-blocker pindolol was studied in 32 subjects in a crossover study comparing pindolol (20 mg, twice daily), methylphenidate, and placebo (Buitelaar et al., 1996). Pindolol significantly reduced ADHD symptoms, but two subjects developed nightmares and hallucinations on the medication. Because lower doses were not examined in this study, it is possible that lower doses may be effective and better tolerated. 

ACE). Hence, angiotensin II production is inhibited. Decrease in angiotensin II results in dilatation of peripheral vessels leading to a reduction in systemic vascular resistance and a decreased aldosterone secretion. They can be administered safely in patients of hypertension with diabetes mellitus or bronchial asthma. ACE inhibitors are efficacious drugs, are well tolerated and are useful antihypertensive drugs. ACE inhibitors are also used in coronary artery... 

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