BLACK BOX WARNING
- abrupt withdrawal
atenolol
Brand: Tenormin
⚠ BBW Prototype: metoprolol-succinate
Drug Class: beta-blocker
Drug Family: antihypertensive
Subclass: selective beta-1 blocker (hydrophilic)
Organ Systems: cardiovascular
Mechanism of Action
Cardioselective beta-1 antagonist; hydrophilic — does not cross BBB; reduced CNS side effects.
beta-1 adrenergic receptor
Indications
- hypertension
- angina
- post-MI
Contraindications
- severe bradycardia
- high-degree AV block
- cardiogenic shock
- decompensated HF
Adverse Effects
Common
- bradycardia
- fatigue
- cold extremities
Serious
- bronchospasm
- heart block
Pharmacokinetics (ADME)
| Absorption | 50% oral bioavailability; not affected by food |
| Distribution | hydrophilic — low CNS penetration |
| Metabolism | minimal hepatic; excreted largely unchanged |
| Excretion | renal 85% |
| Half-life | 6-7 hours |
| Onset | 1 hour |
| Peak | 2-4 hours |
| Duration | 24 hours |
| Protein Binding | 6-16% |
| Vd | 0.7 L/kg |
Drug Interactions
| Drug / Agent | Mechanism | Severity |
|---|---|---|
| verapamil/diltiazem | additive AV block | major |
| clonidine | rebound hypertension on discontinuation | major |
Nursing Considerations
- Hydrophilic — less insomnia and depression than lipophilic beta-blockers
- Requires dose adjustment in renal impairment
- Once-daily dosing
- ASCOT trial: inferior to amlodipine-based regimen for CV outcomes in hypertension
Clinical Pearls
- Hydrophilic — favored in patients with CNS-related beta-blocker side effects (insomnia, nightmares)
- NOT preferred over succinate for HFrEF
- Requires renal dose adjustment unlike lipophilic agents
Safety Profile
Pregnancy use-with-caution
Lactation use-with-caution
Renal Adjustment Required
Hepatic Adjustment Not required
TDM Not required
Concordance Terms
Cross-referenced clinical concepts — click any term to see all content where it appears.