Guanfacine dosing

T Blood pressure and stimulant Give clonidine or guanfacine 4- Dose or change to another medication Same as above but with baseline and... 

Antidepressants and clonidine are the most commonly used augmentation strategies for ADHD. If the patient has tics or is troubled by insomnia, clonidine is a reasonable choice. After collecting a baseline EKG, clonidine should be started at 0.05 mg at bedtime for children and adolescents and 0.1 mg at bedtime for adults. The dose can be increased every 2 weeks or so while monitoring the patient s blood pressure and pulse. Although it has not been studied as well, guanfacine may work in much the same manner as clonidine. 

Dosing of guanfacine reflects its lower potency and longer duration of action. Doses range from 0.5 to 4 mg/day (Chappell et ah, 1995 Hunt et ah, 1995 Sca-hill et ah, 2001), generally administered on a bid or tid schedule. Like clonidine, the dose can be increased by 0.5 mg every 3 to 4 days. The modal total daily dose used by Scahill and colleagues (2001) in a controlled study of ADHD -I- TS was 2.5 mg/day, given tid. 

Guanfacine (open) Hunt et al., 1995 ADHD Mean dose 3.2 mg/day... 

Give dose earlier in the day lower the last dose of the day or give it earlier consider a sedating medication at bedtime (guanfacine or clonidine)... 

The most common side effect of clonidine is dose-dependent sedation that usually subsides after 2 to 3 weeks of therapy. Of concern are reports of bradycardia, rebound hypertension, heart block, and sudden death. Four children have died on the combination of methylphenidate and clonidine however, complicating factors make it impossible to link the drug combination directly with the cause of death. Of 10,060 children exposed to clonidine and assessed by a poison control center over a 7-year period, moderate (19%) to major (2%) toxic effects (bradycardia, hypotension, and respiratory depression) including one death were reported. Overdoses, concurrent clonidine and stimulant administration, as well as missed doses of clonidine aU add to the risk of adverse cardiovascular events. Similar adverse-effect concerns apply to treatment with guanfacine, although its U2a selectivity may result in less sedation and hypotension than clonidine. ... 

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