Guanfacine

What is guanfacine?

Guanfacine is a medication designed to treat high blood pressure, though perhaps better known as a treatment for ADHD. It is also sometimes prescribed to people with opioid use disorder to help with the effects of withdrawal.

Guanfacine lowers blood pressure by slightly decreasing your heart rate and making your blood vessels larger. It is not known exactly how or why it helps with ADHD.

Guanfacine is only available with a prescription from your health care provider. Brand names include Intuniv and Tenex.

Guanfacine is safe when you use it according to the directions from you doctor or other health care provider. Guanfacine can be harmful if:

• Someone takes more than the intended amount.
• Someone takes guanfacine when it is not prescribed to them. This can include situations such as a child getting into their older sibling or parent’s medication.

What happens if you take too much guanfacine?

Taking too much guanfacine, or taking guanfacine that is not prescribed for you, can make you feel very drowsy or lethargic, and lower your heart rate and blood pressure. These symptoms can be serious in some cases, usually only instances involving young children, who may also have trouble breathing due to the guanfacine.

The effects of guanfacine poisoning can sometimes be delayed for hours. A young child who swallows guanfacine may look fine at first and then have serious problems later.

What should I do if someone has taken too much guanfacine, or taken guanfacine that is not prescribed to them?

If someone has taken guanfacine in a way that could be harmful, call the poison center at 1-800-222-1222, chat online above, or text POISON to 85511. If you can, have the medication bottle with you when you contact us.

How can I prevent guanfacine poisonings?

To prevent poisonings from guanfacine:

• Read the label on the bottle each time you take a medication or give it to a child. The label will tell you what the medication is, what it is for, how much to take, and about possible problems you may have. Reading the label each time helps to keep you from making mistakes, such as giving the wrong medication to the wrong person.
• Put guanfacine away immediately after taking it or giving it to your child. Do not leave doses out to be taken later. Many poisonings involve young children who get into medication that was left out for someone else in the house, such as an older sibling.
• Store guanfacine up high, out of reach of children and pets, in a locked cabinet if possible.
• If you have guanfacine that’s expired or that you no longer need, get rid of it safely as soon as possible.