Atenolol

Cardiovascular Drug

Drug class: Beta blockers

Atenolol (TENORMIN)（中文：阿替洛爾）

Pronunciation

Atenolol 100mg

Atenolol 50mg

Common Strengths of Atenolol

Atenolol is available in the following strengths:

• 25 mg
• 50 mg
• 100 mg [1]

Drug Trade Names of Atenolol

The brand names for Atenolol is Tenormin.

Mechanism of Action

Atenolol is a beta1-selective (cardioselective) beta-blocker. It blocks the action of the hormone epinephrine (adrenaline) on the beta-1 receptors in the heart. This slows the heart rate, reduces the force of heart contractions, and decrease blood pressure. This preferential effect is not absolute, however, and at higher doses, atenolol inhibits beta2-adrenoreceptors, chiefly located in the bronchial and vascular musculature.[2]

Route of Administration

Atenolol is available as an oral tablet for oral administration.[1]

Dosages

• Hypertension
  • Initial dose of 50 mg once daily, may be increased to 100 mg once daily if needed.[3]
• Angina
  • 25-50 mg once daily, maintenance 50-200 mg once daily, max 200 mg/day [3]
• Heart failure
  • Dosage not specified
• Diabetic kidney disease
  • Dosage should be adjusted based on creatinine clearance. Significant accumulation occurs when creatinine clearance falls below 35 mL/min.[2]

Side Effects

Frequency	Adverse reactions
Very common (≥1/10)	Bradycardia
Common (≥1/100 to <1/10)	Cold hands and feet
	Diarrhoea
	Nausea
	Fatigue[1]
Uncommon (≥1/1,000 to <1/100)	Depression
	Disturbed sleep[1]

Pharmacokinetics

• Well absorbed from GI tract
• Peak plasma levels in 2-4 hours
• Extensively metabolized in liver
• Elimination half-life 6-7 hours
• Excreted in urine

Drug Management

Safety

• Atenolol has a boxed warning about not stopping it suddenly, as it may worsen chest pain, increase blood pressure, or cause a heart attack. Stopping should be done gradually under medical supervision.[1]
• Contraindicated in certain heart conditions like heart block, bradycardia, heart failure.
• Caution in asthma, diabetes, thyroid disorders.

Pregnancy

Atenolol is a category D pregnancy drug, indicating studies show risk of adverse effects to the fetus. Benefits may outweigh risks in some cases. Discuss with your doctor.[1]

Breast Feeding

Present in breast milk at low levels. Caution advised.

Children and Elderly

• Children: Safety and efficacy not established
• Elderly: May require lower doses due to age-related kidney impairment

Renal Impairment

Dosage should be adjusted based on creatinine clearance, as atenolol is primarily eliminated by the kidneys.[2]

Monitoring Requirements

Monitor heart rate, blood pressure, kidney function.[1]

Drug Interactions

• Calcium channel blockers may increase atenolol levels
• NSAIDs may decrease antihypertensive effect
• Antiarrhythmics may potentiate bradycardia

FAQs

How should I take the tablet?

Take atenolol tablets by mouth, usually once daily, with or without food.[3]

What should I avoid while taking?

Avoid stopping atenolol suddenly without medical supervision. Avoid operating machinery or driving if atenolol makes you dizzy.[3]

What happens if I miss a dose?

If you miss a dose of atenolol, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose.[3]

Reference

[1] https://www.healthline.com/health/drugs/atenolol-oral-tablet

[2] https://www.drugs.com/pro/atenolol-tablets.html

[3] https://www.drugs.com/atenolol.html

[4] https://webmd.com/drugs/2/drug-11035/atenolol-oral/details

[5] https://www.nhs.uk/medicines/atenolol/about-atenolol/