"Hardcore Pharmacology" states that calcium channel blockers, or CCBs, are potent antiarrhthymics. CCBs inhibit calcium ions from entering cardiac muscle cells during contraction. This action relaxes the cardiac muscle and causes vasodilation of blood vessels, vastly improving blood flow and oxygen delivery. In children, CCBs are used for high blood pressure, pulmonary edema, hypertrophic cardiomyopathy and heart electrical conduction abnormalities, called arrhythmias.
Verapamil
Generally used for hypertension and hypertrophic cardiomyopathy, verapamil relaxes the heart muscle and reduces the pressure within the left upper chamber of the heart, according to "Nada's Pediatric Cardiology." Children are more tolerant of this drug than older patients. Administration of verapamil significantly reduces the risk of death is in this heart disease.
Verapamil is generally not recommended for infants under one year of age due to rare but possible cardiac arrest and dangerous drops in blood pressure. Other contraindications include heart block, dangerous drop in heart rate known as bradycardia and atrial flutter. Side effects include dizziness, fatigue, constipation, ringing in the ears and seizures. (See also references 2, 3 and 4)
Amlodipine
Amlodipine is ideal for post-kidney transplant high blood pressure, according to "The Johns Hopkins Hospital: The Harriet Lane Handbook." Odorless and tasteless, amlodipine can be made into an oral suspension taken by children only once a day. Child dosing strength starts with 0.1 milligram per kilogram of body weight. Younger children may require higher doses than older children. Drug interactions occur with fluconazole and protease inhibitors. Side effects include headache, nausea, flushing, fatigue and heart palpitations.
Nifedipine
Commonly used in pediatric hypertensive emergencies, nifedipine has no effect on the electrical conduction of the heart, according to "The Johns Hopkins Hospital: The Harriet Lane Handbook." It is important that nifedipine is never given with grapefruit juice, because it may increase the CCB's effects. Caution should be taken in giving nifedipine to a pediatric patients with aortic stenosis and congestive heart failure. Side effects flushing, rapid heart rate, fainting, constipation, thrombocytopenia, anemia and swelling of the extremities.
Warnings
Always consult your child's pediatrician before administering any pharmacological agent. It is vital that you discuss your child's dosing instructions with his pediatrician, especially in connection with heart medications.
References
- "Nada's Pediatric Cardiology"; John Keane, M.D., et al.; 2006
- "The Johns Hopkins Hospital: The Harriet Lane Handbook" 17th ed.; Jason Roberston, M.D. and Nicole Shilkofski, M.D.; 2005
- "Harrison's Principles of Internal Medicine" 17th ed.; Anthony Fauci, M.D., et al., eds.; 2008
- "Hardcore Pharmacology"; Rodrigo Saenz, M.D., et al.; 2006
