What are Calcium channel blockers? Calcium channel blockers are medications that are primarily used to treat cardiac arrhythmias, hypertension, and angina pectoris.
Calcium channel blockers are medications that are primarily used to treat cardiac arrhythmias hypertension and angina pectoris calcium channel blockers are used to a lesser extent for prophylaxis of migraines and for symptomatic treatment of renault’s phenomenon which is caused by reduced blood flow in tiny peripheral vessels finally calcium channel blockers
Also relax uterine smooth muscle which is useful to prevent premature uterine contractions and this can help delay preterm labor now calcium channel blockers can be administered orally or intravenously and are divided into two main groups dihydropyridines and non-dihydropyridines dihydropyridines include amlodipine nocardipine nephetipine phylodepene and
Clavitipine which have a more potent action on the blood vessels specifically the arterials then the heart as a result they’re preferred to treat hypertension another dihydropyridine is pneumotipine which has the added benefit of being able to cross over the blood-brain barrier so it can be used to prevent or treat cerebral vasospasm caused by an aneurysmal
Subarachnoid hemorrhage on the other hand non-dihydropyridines include varapamil and diltiazem which have a more potent action on the heart than the blood vessels varapamil is highly selective for cardiac calcium channels and thus is mainly used to treat angina pectoris and arrhythmias diltiazem is equally good at blocking both cardiac and vascular calcium
Channels so it’s effective in hypertension and arrhythmias now once administered calcium channel blockers block voltage-gated calcium channels and they act by decreasing the amount of calcium entering the cell normally calcium is required for the contraction of both the cardiac muscles and the vascular smooth muscles so the decreased calcium reduces the muscles
Ability to contract ultimately relaxing them now calcium channel blockers relax vascular particularly arterial smooth muscles which helps reduce the blood pressure and peripheral vascular resistance or the afterload which is the pressure that the heart must work against to eject the blood at the same time in the heart calcium channel blockers relax the coronary
Vessels which improves the oxygen delivery to the heart and they also reduce the force of contraction of the cardiac muscles which reduces the oxygen demand of the heart additionally calcium channel blockers prevent the depolarization of cardiac pacemaker cells in the sa and av nodes which are responsible for generating and maintaining the heart rate this way
These medications reduce the firing and conduction of the impulses through these nodes eventually decreasing the heart rate now the vasodilatory action of calcium channel blockers may also lead to some side effects including headache dizziness flushing of the skin peripheral edema and hypotension which is more common with dihydropyridines moreover hypotension can
Trigger reflex tachycardia in order to maintain adequate tissue perfusion finally dihydropyridines can also cause gingival hyperplasia the cause of which is still unclear on the other hand non-dihydropyridines decrease the heart rate and contractility so they can cause additional side effects like bradycardia constipation and hyperprolactinemia now due to their
Depressive action on the heart non-dihydropyridines and to a lesser extent dihydropyridines are contraindicated in clients with pre-existing bradycardia heart block and heart failure in addition calcium channel blockers should be used cautiously in clients with hepatic or renal disease as well as when combined with digoxin which is an antiarrhythmic medication
As clients can develop digoxin toxicity by reducing its action and elimination finally clients on calcium channel blockers must avoid consuming grapefruit as their interaction can result in toxicity now if your client is prescribed a calcium channel blocker be sure to obtain their baseline heart rate and blood pressure and review their lab results including cbc
Sodium potassium creatinine bun liver function tests and urinalysis as well as their electrocardiogram or ecg if your client is taking a calcium channel blocker for angina pectoris remember to ask them about the frequency and severity of their anginal symptoms be sure your client understands how the medication helps control their symptoms and instruct them to take
Their medication exactly as instructed and to not stop taking it abruptly let them know that they can take their medication with or without food and that extended release tablets should not be divided crushed or chewed stress the importance of avoiding grapefruit and grapefruit juice which can increase the blood level of their medication and advise them to limit
Caffeine consumption as well since it can increase blood pressure and heart rate then teach your client how to take their pulse and blood pressure and to contact their health care provider if they experience hypotension or bradycardia if their medication is prescribed for angina stress the importance of seeking medical assistance immediately if they experience
Angina that is not relieved by rest or medication finally reinforce cardiovascular health promotion by teaching your client about lifestyle modifications such as maintaining a healthy weight smoking cessation reducing their intake of sodium and alcohol and increasing physical activity next talk to your client about how to manage the common side effects of calcium
Channel blockers let them know that they may experience dizziness hypotension and reflex tachycardia and that they should change positions slowly to prevent falls if your client develops peripheral edema in the ankles and feet encourage them to elevate their legs for a few hours each day remind your client how increasing their daily intake of fluid and fiber can
Help reduce the risk of constipation also stress the importance of good dental hygiene to prevent gingival hyperplasia lastly prompt your client to contact their healthcare provider if any of these adverse effects are persistent or become bothersome during treatment monitor your clients blood pressure heart rate and angina symptoms for therapeutic effects of
The medication finally continue to monitor for side effects and report any changes in the client’s condition to the health care provider all right as a quick recap calcium channel blockers are medications that are used to treat cardiac arrhythmias hypertension angina pectoris and other conditions these medications work by blocking calcium channels in the vascular
Smooth muscles and cardiac muscles which in turn helps them to relax non-dihydropyridines have a more potent action on the heart than dihydropyridines so they are used more often to treat arrhythmias and angina pectoris while dihydropyridines exert their effects primarily on the blood vessels so they are more often used to treat hypertension nursing considerations
For calcium channel blockers center around completing a thorough baseline assessment providing client education for safe self-administration and dealing with side effects such as hypotension bradycardia and constipation promoting cardiovascular health and evaluating the therapeutic response helping current and future clinicians focus learn retain and thrive learn more you
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Calcium channel blockers: Nursing Pharmacology By Osmosis
