快樂小藥師 Im pharmacist nichts glücklich

Guanadrel（Hylorel）

是的，看名字又知道他跟降血壓有關了

不過跟之前的Guanabenz不同的是他是針對中重度高血壓的治療，而且通常會合併其他的將血壓藥物，像是利尿劑之類的。

機轉：

Guanadrel sulfate is an adrenergic neuron inhibitor that is similar to guanethidine, bethanidine, and debrisoquine. Like these agents, guanadrel lowers arterial pressure secondary to decreased peripheral vascular resistance and cardiac output by depletion of catecholamines from adrenergic nerve endings, the myocardium, and vascular walls (Pascual & Julius, 1972a; Cangiano & Bloomfield, 1969a). As with guanethidine, the hypotensive effects of guanadrel are most pronounced in the erect position (Bloomfield & Cangiano, 1970a). On a weight basis, guanadrel is about one-third as potent as guanethidine (Bloomfield & Cangiano, 1970a).

用法：

The manufacturer recommends a starting dose of 10 mg/day which should be administered as 5 mg twice daily. Dosage should be adjusted weekly or monthly until blood pressure is controlled. The usual effective dosage range is 20 to 75 mg/day. Higher dosages should be administered either 3 or 4 times a day (Prod Info Hylorel(R), 1994; Pascual & Julius, 1972c).
Recommended doses in hypertension are 10 mg orally daily initially (in combination with diuretics), increasing weekly by 10-mg increments. Most patients can be controlled with doses of 20 to 75 mg daily, but some may require doses as high as 400 mg/day. The daily dose should be divided and administered in the morning and evening (Finnerty & Brogden, 1985c); (Chrysant & Trollich, 1976).
Mean daily doses of 55 mg have been correlated with effective antihypertensive responses after 8 and 12 weeks of therapy in patients with mild, moderate, or severe hypertension (Dunn & Dunlap, 1981a). The dose of guanadrel must be titrated to optimal response at weekly intervals.

最大劑量：
Doses of guanadrel should not exceed 400 mg daily (Prod Info Hylorel(R), 1994; Finnerty & Brogden, 1985c).

合併治療時：
COMBINATION THERAPY
a)  The effectiveness of adding guanadrel to a diuretic and a beta-blocker was evaluated in 27 patients with inadequately controlled hypertension (Gore, 1983). Guanadrel was added and titrated to normalize blood pressure after the patients had failed to respond during the previous 6 weeks to the combination of hydrochlorothiazide 100 mg/day, and propranolol titrated to 480 mg/day. All patients were effectively treated with doses ranging from 10 to 80 mg/day, the average being 40 mg/day. A mean sitting and supine blood pressure decrease of 24.8/19.4 mmHg and 19.8/15.8 mmHg occurred, respectively, over an 8- to 12-week period after the initiation and titration of the guanadrel dose.

腎功能不好時要調整劑量：

CCr：30-60mL/min 每24小時給5mg，每七天調整一次

CCr<30：每48小時給5mg，每14天調整一次

懷孕等級：b

Pharmacokinetics

Absorption
T max is 1.5 to 2 h.

Elimination
T 1/ 2 is about 10 h. About 85% is excreted in the urine, about 40% as unchanged drug.