Antithyroid Drugs And Other Thyroid Inhibitors

A large number of compounds interfere either directly or indirectly with the synthesis, release, or action of thyroid hormones (Table 56-2). Inhibitors are classified into four categories (1) antithyroid drugs, which interfere directly with the synthesis of thyroid hormones (2) ionic inhibitors, which block the iodide transport mechanism (3) high concentrations of iodine itself, which decrease release of thyroid hormones and may also decrease hormone synthesis and (4) radioactive iodine, which...

A1 Adrenergic Antagonists

Drugs that selectively block a1 adrenergic receptors without affecting a2 adrenergic receptors also are used in hypertension (Table 32-2). Prazosin (minipress), terazosin (Hytrin), and doxazosin (Cardura) are the agents approved in the U.S. for this indication. PHARMACOLOGICAL EFFECTS Initially, a1 adrenergic receptor antagonists reduce arteriolar resistance and increase venous capacitance this causes a sympathetically mediated reflex increase in heart rate and plasma renin activity. During...

Poorly Absorbed Sulfonamides

Sulfasalazine (azulfidine) is very poorly absorbed from the GI tract and is used in the therapy of ulcerative colitis and Crohn's disease (see Chapter 38). SULFONAMIDES FOR TOPICAL USE Sulfacetamide Sulfacetamide is the N1-acetyl-substituted derivative of sulfanilamide. Its aqueous solubility is 90 times that of sulfadiazine. This drug (isopto-cetamide, others) is employed extensively for ophthalmic infections. Very high aqueous concentrations are not irritating to the eye and are effective...

Parenteral Vasodilators

The failing left ventricle is characterized by depression of myocardial contractility and increased sensitivity to alterations of left ventricular afterload. This latter attribute of the failing ventricle is manifest by a greater proportional reduction of stroke volume as the impedance to ejection is increased. Conversely, afterload reduction in this setting can be associated with substantial increases in stroke volume. This increased afterload dependence underlies the beneficial effects of...

Selection Of Antihypertensive Drugs In Individual Patients

Choice of an antihypertensive drug should be driven by likely benefit in an individual patient, taking into account concomitant diseases such as diabetes mellitus, problematic adverse effects of specific drugs, and cost. Consensus guidelines recommend diuretics as preferred initial therapy for most patients with uncomplicated stage 1 hypertension who are unresponsive to nonpharmacological measures. Patients are also commonly treated with other drugs p receptor antagonists, ACE inhibitors A...

Pharmacotherapy Of Gout

Gout results from the precipitation of urate crystals in the tissues and the subsequent inflammatory response. Acute gout usually causes an exquisitely painful distal monoarthritis, but it also can cause joint destruction, subcutaneous deposits (tophi), and renal calculi and damage. Gout affects -0.5-1 of the population of Western countries. The pathophysiology of gout is understood poorly. While a prerequisite, hyperuricemia does not inevitably lead to gout. Uric acid, the end product of...