Guanadrel Uses, Dosage, Side Effects, Food Interaction and all others data.

Guanadrel is an antihypertensive agent and postganglionic adrenergic blocking agent.

High blood pressure adds to the work load of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled. Guanadrel works by controlling nerve impulses along certain nerve pathways. As a result, it relaxes the blood vessels so that blood passes through them more easily. This helps to lower blood pressure.

Trade Name Guanadrel
Availability Discontinued
Generic Guanadrel
Guanadrel Other Names Guanadrel, Guanadrelum
Related Drugs amlodipine, lisinopril, metoprolol, losartan, furosemide, hydrochlorothiazide
Type Oral
Formula C10H19N3O2
Weight Average: 213.2768
Monoisotopic: 213.147726867
Protein binding

Low, approximately 20%

Groups Approved
Therapeutic Class
Available Country United States
Last Updated: September 19, 2023 at 7:00 am


Used to treat and control hypertension.

How Guanadrel works

Guanadrel is an adrenergic neuron inhibitor that slowly displaces norepinephrine from its storage in nerve endings. It blocks the release of norepinephrine in response to the sympathetic nerve stimulation, leading to reduced arteriolar vasoconstriction, especially the reflex increase in sympathetic tone that occurs with a change in position.


Side effects include dizziness, drowsiness, headache, constipation, diarrhea, gas pains, loss of appetite, fatigue, and nasal congestion.

Guanadrel Alcohol interaction


Many psychotherapeutic and CNS-active agents (e.g., anxiolytics, sedatives, hypnotics, antidepressants, antipsychotics, opioids, alcohol, muscle relaxants) exhibit hypotensive effects, especially during initiation of therapy and dose escalation.

Coadministration with antihypertensives and other hypotensive agents, in particular vasodilators and alpha-blockers, may result in additive effects on blood pressure and orthostasis.

Caution and close monitoring for development of hypotension is advised during coadministration of these agents.

Some authorities recommend avoiding alcohol in patients receiving vasodilating antihypertensive drugs.

Patients should be advised to avoid rising abruptly from a sitting or recumbent position and to notify their physician if they experience dizziness, lightheadedness, syncope, orthostasis, or tachycardia.

Guanadrel Disease Interaction

Moderate: peripheral edema

Elimination Route

Rapidly and readily absorbed from the gastrointestinal tract.

Half Life

10 hours

Innovators Monograph

You find simplified version here Guanadrel

*** Taking medicines without doctor's advice can cause long-term problems.