guanfacine (Intuniv, Tenex) (cont.)
Omudhome Ogbru, PharmD
Omudhome Ogbru, PharmD
Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.
Medical and Pharmacy Editor:
STORAGE: Tablets should be stored at room temperature, between 15 C to 30 C (59 F to 86 F).
PRESCRIBED FOR: Extended release guanfacine (Intuniv) is used alone or in combination with other medications for the treatment of ADHD. Immediate release guanfacine (Tenex) is used alone or in combination with other medications for the treatment of high blood pressure.
DRUG INTERACTIONS: Rifampin and St. John's wort may reduce blood levels of guanfacine by increasing its metabolism (breakdown) in the intestine; doses of guanfacine may need to be increased when combined with drugs that reduce its blood levels.
Other drugs that also may reduce blood levels of guanfacine include carbamazepine (Tegretol, Tegretol XR , Equetro, Carbatrol, Epitol, Teril), phenytoin (Dilantin, Dilantin-125), phenobarbital, oxcarbazepine (Trileptal), rifabutin, rifampin, rifapentine, bosentan (Tracleer), and tipranavir/ritonavir (Aptivus).
Ketoconazole (Nizoral, Extina, Xolegel, Kuric), itraconazole (Sporanox), and simeprevir (Olysio) may increase blood levels of guanfacine by decreasing its metabolism in the intestine; the dose of guanfacine may need to be decreased when combined with drugs that increase its blood levels.
PREGNANCY: Guanfacine has not been adequately evaluated in pregnant women. Due to the lack of safety data, guanfacine should be used cautiously during pregnancy, taking into account the potential benefits and risks of therapy. Guanfacine is classified as FDA pregnancy risk B.
Medically Reviewed by a Doctor on 4/16/2014
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Need help identifying pills and medications?
Back to Medications Index