Atenolol is a beta blocker medication primarily used to treat high blood pressure and heart-associated chest pain.
[10] Common side effects include feeling tired, heart failure, dizziness, depression, and shortness of breath.
[17] The role for β-blockers in general in hypertension was downgraded in June 2006 in the United Kingdom, and later in the United States, as they are less appropriate than other agents such as ACE inhibitors, calcium channel blockers, thiazide diuretics and angiotensin receptor blockers, particularly in the elderly.
[22][23] β-blockers, of which atenolol is mainly studied, provides weaker protection against stroke and mortality in patients over 60 years old compared to other antihypertensive medications.
These include bradycardia (slow heartbeat), severe hypotension with shock, acute heart failure, hypoglycemia and bronchospastic reactions.
Atropine will counteract bradycardia, glucagon helps with hypoglycemia, dobutamine can be given against hypotension and the inhalation of a β2-mimetic such as hexoprenalin or salbutamol will terminate bronchospasms.
Blood or plasma atenolol concentrations may be measured to confirm a diagnosis of poisoning in hospitalized patients or to assist in a medicolegal death investigation.
[30][31] Interactions with atenolol include catecholamine-depleting drugs like reserpine, calcium channel blockers, disopyramide, amiodarone, clonidine, prostaglandin synthase inhibitors like indomethacin, and digitalis glycosides.
[32][5][33] As a result, it has little or no potential for cytochrome P450-related drug interactions, for instance with inhibitors and inducers of these enzymes.
[5] Beta blockers like atenolol can reduce or block the cardiovascular effects of sympathomimetics and amphetamines, such as hypertension and tachycardia.
[4] The general effects of atenolol, including beta-blocking and antihypertensive effects, last for at least 24 hours following oral doses of 50 or 100 mg.[4] With intravenous administration, maximal reduction in exercise-related tachycardia occurs within 5 minutes and following a single 10 mg dose has dissipated within 12 hours.
[4] The pharmacokinetic profile of atenolol results in it having relatively consistent plasma drug levels with about 4-fold variation between individuals.
[4] Atenolol is classified as a beta blocker with low lipophilicity and hence lower potential for crossing the blood–brain barrier and entering the brain.
Atenolol has been given as an example of how slow healthcare providers are to change their prescribing practices in the face of medical evidence that indicates that a drug is not as effective as others in treating some conditions.
[48] Although the number of prescriptions has been declining steadily since limited evidence articles contesting its efficacy was published, it has been estimated that it would take 20 years for doctors to stop prescribing it for hypertension.
[48] Despite its diminished efficacy when compared to newer antihypertensive drugs, atenolol and other beta blockers are still a relevant clinical choice for treating some conditions, since beta blockers are a diverse group of medicines with different properties that still requires further research.