Phenylpropanolamine belongs to the sympathomimetic amine class of drugs and is structurally related to ephedrine. The effects of phenylpropanolamine are largely the result of alpha-adrenergic agonist activity resulting from both direct stimulation of adrenergic receptors and release of neuronal norepinephrine. Phenylpropanolamine is mainly used as a nasal decongestant. Phenylpropanolamine is also used as anorexiant in obesity and to treat urinary incontinence in veteranary. Phenylpropanolamine containing products has been withdrawn by FDA due to the association of phenylpropanolamine use with increased risk of hemorrhagic stroke.

Indoramin is an alpha-1 selective antagonist of adrenergic receptor, sold under trade names Baratol and Doralese, and now available as a generic. It has no reflex tachycardia and direct myocardial depression action and is used to treat benign prostate hyperplasia (as 20 mg tablets) or reduce blood pressure (as 25 mg strength tablets). It was also investigated as a treatment of a migraine and congestive heart failure.

Alfuzosin is a quinazoline-derivative alpha-adrenergic blocking agent used to treat hypertension and benign prostatic hyperplasia. Alfuzosin is marketed in the United States by Sanofi Aventis under the brand name Uroxatral. UROXATRAL (alfuzosin HCl extended-release tablets) is indicated for the treatment of the signs and symptoms of benign prostatic hyperplasia. UROXATRAL is not indicated for the treatment of hypertension. Alfuzosin is a non-subtype specific alpha(1)-adrenergic blocking agent that exhibits selectivity for alpha(1)-adrenergic receptors in the lower urinary tract. Inhibition of these adrenoreceptors leads to the relaxation of smooth muscle in the bladder neck and prostate, resulting in the improvement in urine flow and a reduction in symptoms in benign prostate hyperplasia. Alfuzosin also inhibits the vasoconstrictor effect of circulating and locally released catecholamines (epinephrine and norepinephrine), resulting in peripheral vasodilation.

Doxazosin mesylate is a quinazoline compound sold by Pfizer under the brand name CARDURA. CARDURA is indicated for the treatment of both the urinary outflow obstruction and obstructive and irritative symptoms associated with BPH: obstructive symptoms (hesitation, intermittency, dribbling, weak urinary stream, incomplete emptying of the bladder) and irritative symptoms (nocturia, daytime frequency, urgency, burning). CARDURA may be used in all BPH patients whether hypertensive or normotensive. In patients with hypertension and BPH, both conditions were effectively treated with CARDURA monotherapy. CARDURA provides rapid improvement in symptoms and urinary flow rate in 66–71% of patients. CARDURA is also indicated for the treatment of hypertension. CARDURA may be used alone or in combination with diuretics, beta-adrenergic blocking agents, calcium channel blockers, or angiotensin-converting enzyme inhibitors. Doxazosin acts by inhibiting the postsynaptic alpha(1)-adrenoceptors on vascular smooth muscle. This inhibits the vasoconstrictor effect of circulating and locally released catecholamines (epinephrine and norepinephrine), resulting in peripheral vasodilation.

Doxazosin mesylate is a quinazoline compound sold by Pfizer under the brand name CARDURA. CARDURA is indicated for the treatment of both the urinary outflow obstruction and obstructive and irritative symptoms associated with BPH: obstructive symptoms (hesitation, intermittency, dribbling, weak urinary stream, incomplete emptying of the bladder) and irritative symptoms (nocturia, daytime frequency, urgency, burning). CARDURA may be used in all BPH patients whether hypertensive or normotensive. In patients with hypertension and BPH, both conditions were effectively treated with CARDURA monotherapy. CARDURA provides rapid improvement in symptoms and urinary flow rate in 66–71% of patients. CARDURA is also indicated for the treatment of hypertension. CARDURA may be used alone or in combination with diuretics, beta-adrenergic blocking agents, calcium channel blockers, or angiotensin-converting enzyme inhibitors. Doxazosin acts by inhibiting the postsynaptic alpha(1)-adrenoceptors on vascular smooth muscle. This inhibits the vasoconstrictor effect of circulating and locally released catecholamines (epinephrine and norepinephrine), resulting in peripheral vasodilation.

Prazosin (trade names Minipress, Vasoflex, Lentopres, and Hypovase) is a selective α-1-adrenergic receptor antagonist used to treat hypertension. Prazosin acts by inhibiting the postsynaptic alpha-1-adrenoceptors on vascular smooth muscle. This inhibits the vasoconstrictor effect of circulating and locally released catecholamines (epinephrine and norepinephrine), resulting in peripheral vasodilation. Prazosin is orally active and has a minimal effect on cardiac function due to its alpha-1 receptor selectivity. However, when prazosin is started, heart rate and contractility go up in order to maintain the pre-treatment blood pressures because the body has reached homeostasis at its abnormally high blood pressure. The blood pressure lowering effect becomes apparent when prazosin is taken for longer periods of time. The heart rate and contractility go back down over time and blood pressure decreases. The antihypertensive characteristics of prazosin make it a second-line choice for the treatment of high blood pressure. Prazosin is also useful in treating urinary hesitancy associated with prostatic hyperplasia, blocking alpha-1 receptors, which control constriction of both the prostate and urethra. Although not a first line choice for either hypertension or prostatic hyperplasia, it is a choice for patients who present with both problems concomitantly. Common (4–10% frequency) side effects of prazosin include dizziness, headache, drowsiness, lack of energy, weakness, palpitations, and nausea. Less frequent (1–4%) side effects include vomiting, diarrhea, constipation, edema, orthostatic hypotension, dyspnea, syncope, vertigo, depression, nervousness, and rash.

Berefrine (also known as phenylephrine oxazolidine), a prodrug of phenylephrine, is a mydriatic agent. Berefrine was developed for improving ocular absorption and reducing systemic side effects.

Berefrine (also known as phenylephrine oxazolidine), a prodrug of phenylephrine, is a mydriatic agent. Berefrine was developed for improving ocular absorption and reducing systemic side effects.

Berefrine (also known as phenylephrine oxazolidine), a prodrug of phenylephrine, is a mydriatic agent. Berefrine was developed for improving ocular absorption and reducing systemic side effects.