DOSAGE AND ADMINISTRATION
The recommended initial dose of Tenex (guanfacine hydrochloride) when given alone or in combination with another antihypertensive drug is 1 mg daily given at bedtime to minimize somnolence. If after 3 to 4 weeks of therapy 1 mg does not give a satisfactory result, a dose of 2 mg may be given, although most of the effect of Tenex is seen at 1 mg (see CLINICAL PHARMACOLOGY). Higher daily doses have been used, but adverse reactions increase significantly with doses above 3 mg/day.
The frequency of rebound hypertension is low, but it can occur. When rebound occurs, it does so after 2 - 4 days, which is delayed compared with clonidine hydrochloride. This is consistent with the longer half-life of guanfacine. In most cases, after abrupt withdrawal of guanfacine, blood pressure returns to pretreatment levels slowly (within 2 - 4 days) without ill effects.
Tenex® (guanfacine hydrochloride) Tablets are available in the following dosing strengths (expressed in equivalent amounts of guanfacine):
1 mg - light pink, diamond-shaped tablet embossed with a 1 and engraved RP on one side and engraved TENEX on the other side in bottles of 100 (NDC 67857-705-01) and 500 (NDC 67857-705-05).
2 mg—yellow, diamond-shaped tablet, one side engraved TENEX, other side engraved 2 with RP below it in bottles of 100 (NDC 67857-706-01).
Store at controlled temperature, between 20 and 25°C (68°F and 77°F).
Dispense in a tight, light-resistant container.
Distributed by: Promius Pharma, LLC Bridgewater, NJ 08807. Manufactured by: Patheon, Puerto Rico, Inc. Manati, Puerto Rico 00674, USA. Revised: July 2013
Last reviewed on RxList: 7/18/2013
This monograph has been modified to include the generic and brand name in many instances.
Additional Tenex Information
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