Penbutolol

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

Penbutolol is a drug in the beta-blocker class used to treat hypertension. Penbutolol binds both beta-1 and beta-2 adrenergic receptors, rendering it a non-selective beta-blocker. Penbutolol can act as a partial agonist at beta adrenergic receptors, since it is a sympathomimetric drug. Penbutolol also demonstrates high binding affinity to the 5-hydroxytryptamine receptor 1A with antagonistic effects. This binding characteristic of penbutolol is being investigated for its implications in Antidepressant Therapy. Penbutolol is contraindicated in patients with cardiogenic shock, sinus bradycardia, second and third degree atrioventricular conduction block, bronchial asthma, and those with known hypersensitivity.

Penbutolol is a ß-1, ß-2 (nonselective) adrenergic receptor antagonist. Experimental studies showed a dose-dependent increase in heart rate in reserpinized (norepinephrine-depleted) rats given penbutolol intravenously at doses of 0.25 to 1.0 mg/kg, suggesting that penbutolol has some intrinsic sympathomimetic activity. In human studies, however, heart rate decreases have been similar to those seen with propranolol.

Penbutolol
Uses
Dosage
Side Effect
Precautions
Interactions
Uses during Pregnancy
Uses during Breastfeeding
Accute Overdose
Food Interaction
Half Life
Volume of Distribution
Clearance
Interaction With other Medicine
Contradiction
Storage

Trade Name	Penbutolol
Availability	Discontinued
Generic	Penbutolol
Penbutolol Other Names	Penbutolol, Penbutololum
Related Drugs	amlodipine, aspirin, lisinopril, metoprolol, losartan, furosemide, hydrochlorothiazide, atenolol, diltiazem, nitroglycerin
Type	Oral
Formula	C₁₈H₂₉NO₂
Weight	Average: 291.4284 Monoisotopic: 291.219829177
Protein binding	80-98% bound to plasma proteins. Extensively bound to Alpha-1-acid glycoprotein 1.
Groups	Approved, Investigational
Therapeutic Class
Manufacturer
Available Country	United States
Last Updated:	September 19, 2023 at 7:00 am

Uses

Penbutolol is a beta-adrenergic antagonist used for the management of mild to moderate arterial hypertension, alone or in combination with other antihypertensive agents.

Penbutolol is indicated in the treatment of mild to moderate arterial hypertension. It may be used alone or in combination with other antihypertensive agents, especially thiazide-type diuretics.Penbutolol is contraindicated in patients with cardiogenic shock, sinus bradycardia, second and third degree atrioventricular conduction block, bronchial asthma, and those with known hypersensitivity.

How Penbutolol works

Penbutolol acts on the β1 adrenergic receptors in both the heart and the kidney. When β1 receptors are activated by catecholamines, they stimulate a coupled G protein that leads to the conversion of adenosine triphosphate (ATP) to cyclic adenosine monophosphate (cAMP). The increase in cAMP leads to activation of protein kinase A (PKA), which alters the movement of calcium ions in heart muscle and increases the heart rate. Penbutolol blocks the catecholamine activation of β1 adrenergic receptors and decreases heart rate, which lowers blood pressure.

Toxicity

Symptoms of overdose include drowsiness, vertigo, headache, and atriventricular block.

Penbutolol Alcohol interaction

[Moderate]

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.

Penbutolol Cholesterol interaction

[Moderate] Beta-adrenergic receptor blocking agents (aka beta-blockers) may alter serum lipid profiles.

Increases in serum VLDL and LDL cholesterol and triglycerides, as well as decreases in HDL cholesterol, have been reported with some beta-blockers.

Patients with preexisting hyperlipidemia may require closer monitoring during beta-blocker therapy, and adjustments made accordingly in their lipid-lowering regimen.

Penbutolol multivitamins interaction

[Moderate] ADJUST DOSING INTERVAL: Concurrent administration with calcium salts may decrease the oral bioavailability of atenolol and possibly other beta-blockers.

The exact mechanism of interaction is unknown.

In six healthy subjects, calcium 500 mg (as lactate, carbonate, and gluconate) reduced the mean peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) of atenolol (100 mg) by 51% and 32%, respectively.

The elimination half-life increased by 44%.

Twelve hours after the combination, beta-blocking activity (as indicated by inhibition of exercise tachycardia) was reduced compared to that with atenolol alone.

However, during a 4-week treatment in six hypertensive patients, there was no difference in blood pressure values between treatments.

The investigators suggest that prolongation of the elimination half-life induced by calcium coadministration may have led to atenolol cumulation during long-term dosing, which compensated for the reduced bioavailability.

It may help to separate the administration times of beta-blockers and calcium products by at least 2 hours.

Patients should be monitored for potentially diminished beta-blocking effects following the addition of calcium therapy.