Guanadrel is an adrenergic blocker that's used to treat high blood pressure. It works by [preventing the release](https://www.heart.org/en/health-topics/high-blood-pressure/changes-you-can-make-to-manage-high-blood-pressure/types-of-blood-pressure-medications) of certain chemicals that normally make your blood vessels tighten. By blocking this release, guanadrel causes your blood vessels to open up, which lowers your blood pressure.

Is guanadrel still available?

No, guanadrel has been [discontinued](https://www.accessdata.fda.gov/scripts/cder/daf/index.cfm?event=overview.process&ApplNo=18104) and is no longer available in the United States. It's not exactly clear why it was discontinued.

Are there currently available medications that are used in place of guanadrel?

Yes, there are several available [medications used to treat high blood pressure](https://www.goodrx.com/conditions/hypertension/high-blood-pressure-medications) that are commonly used today. Examples include [ACE inhibitors](https://www.goodrx.com/classes/ace-inhibitors) (e.g., [lisinopril (Zestril)](https://www.goodrx.com/lisinopril/what-is)) and [beta blockers](https://www.goodrx.com/classes/beta-blockers) (e.g., [metoprolol (Lopressor)](https://www.goodrx.com/metoprolol/what-is)).

Hylorel

guanadrel

Used for Hypertension

Guanadrel is a medication used for treating high blood pressure. It's no longer available in the United States because it was discontinued.

Reviewed by:

Robert Chad Hakim, PharmD, BCCCP

Allison Gourley, PharmD

Last reviewed on June 29, 2022

What is Guanadrel?

What is Guanadrel used for?

High blood pressure

Are you looking for information on guanfacine or guaifenesin (Mucinex) instead?

Drug facts

Common Brands	Hylorel(brand no longer available)
Drug Class	Adrenergic blocker
Controlled Substance Classification	Not a controlled medication
Generic Status	No lower-cost generic available
Availability	Discontinued

Common Brands

Hylorel(brand no longer available)

Drug Class

Adrenergic blocker

Controlled Substance Classification

Not a controlled medication

Generic Status

No lower-cost generic available

Availability

Discontinued

Common questions about Hylorel

Hylorel is an adrenergic blocker that's used to treat high blood pressure. It works by preventing the release of certain chemicals that normally make your blood vessels tighten. By blocking this release, Hylorel causes your blood vessels to open up, which lowers your blood pressure.

No, Hylorel has been discontinued and is no longer available in the United States. It's not exactly clear why it was discontinued.

Yes, there are several available medications used to treat high blood pressure that are commonly used today. Examples include ACE inhibitors (e.g., lisinopril (Zestril)) and beta blockers (e.g., metoprolol (Lopressor)).