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Medical and surgical emergencies
Advanced cardiac life support (ACLS): Clinical (To be retired)
Supraventricular arrhythmias: Pathology review
Ventricular arrhythmias: Pathology review
Heart blocks: Pathology review
Coronary artery disease: Clinical (To be retired)
Heart failure: Clinical (To be retired)
Syncope: Clinical (To be retired)
Pericardial disease: Clinical (To be retired)
Valvular heart disease: Clinical (To be retired)
Chest trauma: Clinical (To be retired)
Shock: Clinical (To be retired)
Peripheral vascular disease: Clinical (To be retired)
Leg ulcers: Clinical (To be retired)
Aortic aneurysms and dissections: Clinical (To be retired)
Cholinomimetics: Direct agonists
Cholinomimetics: Indirect agonists (anticholinesterases)
Muscarinic antagonists
Sympathomimetics: Direct agonists
Sympatholytics: Alpha-2 agonists
Adrenergic antagonists: Presynaptic
Adrenergic antagonists: Alpha blockers
Adrenergic antagonists: Beta blockers
ACE inhibitors, ARBs and direct renin inhibitors
Loop diuretics
Thiazide and thiazide-like diuretics
Calcium channel blockers
cGMP mediated smooth muscle vasodilators
Class I antiarrhythmics: Sodium channel blockers
Class II antiarrhythmics: Beta blockers
Class III antiarrhythmics: Potassium channel blockers
Class IV antiarrhythmics: Calcium channel blockers and others
Positive inotropic medications
Antiplatelet medications
Blistering skin disorders: Clinical (To be retired)
Bites and stings: Clinical (To be retired)
Burns: Clinical (To be retired)
Diabetes mellitus: Clinical (To be retired)
Hyperthyroidism: Clinical (To be retired)
Hypothyroidism and thyroiditis: Clinical (To be retired)
Parathyroid conditions and calcium imbalance: Clinical (To be retired)
Adrenal insufficiency: Clinical (To be retired)
Neck trauma: Clinical (To be retired)
Insulins
Mineralocorticoids and mineralocorticoid antagonists
Glucocorticoids
Abdominal pain: Clinical (To be retired)
Appendicitis: Clinical (To be retired)
Gastrointestinal bleeding: Clinical (To be retired)
Peptic ulcers and stomach cancer: Clinical (To be retired)
Inflammatory bowel disease: Clinical (To be retired)
Diverticular disease: Clinical (To be retired)
Gallbladder disorders: Clinical (To be retired)
Pancreatitis: Clinical (To be retired)
Cirrhosis: Clinical (To be retired)
Hernias: Clinical (To be retired)
Bowel obstruction: Clinical (To be retired)
Abdominal trauma: Clinical (To be retired)
Laxatives and cathartics
Antidiarrheals
Acid reducing medications
Blood products and transfusion: Clinical (To be retired)
Venous thromboembolism: Clinical (To be retired)
Anticoagulants: Heparin
Anticoagulants: Warfarin
Anticoagulants: Direct factor inhibitors
Antiplatelet medications
Thrombolytics
Fever of unknown origin: Clinical (To be retired)
Infective endocarditis: Clinical (To be retired)
Pneumonia: Clinical (To be retired)
Tuberculosis: Pathology review
Diarrhea: Clinical (To be retired)
Urinary tract infections: Clinical (To be retired)
Meningitis, encephalitis and brain abscesses: Clinical (To be retired)
Bites and stings: Clinical (To be retired)
Skin and soft tissue infections: Clinical (To be retired)
Protein synthesis inhibitors: Aminoglycosides
Antimetabolites: Sulfonamides and trimethoprim
Antituberculosis medications
Miscellaneous cell wall synthesis inhibitors
Protein synthesis inhibitors: Tetracyclines
Cell wall synthesis inhibitors: Penicillins
Miscellaneous protein synthesis inhibitors
Cell wall synthesis inhibitors: Cephalosporins
DNA synthesis inhibitors: Metronidazole
DNA synthesis inhibitors: Fluoroquinolones
Herpesvirus medications
Azoles
Echinocandins
Miscellaneous antifungal medications
Anthelmintic medications
Antimalarials
Anti-mite and louse medications
Hypernatremia: Clinical (To be retired)
Hyponatremia: Clinical (To be retired)
Hyperkalemia: Clinical (To be retired)
Hypokalemia: Clinical (To be retired)
Metabolic and respiratory acidosis: Clinical (To be retired)
Metabolic and respiratory alkalosis: Clinical (To be retired)
Toxidromes: Clinical (To be retired)
Medication overdoses and toxicities: Pathology review
Environmental and chemical toxicities: Pathology review
Acute kidney injury: Clinical (To be retired)
Kidney stones: Clinical (To be retired)
Adrenergic antagonists: Alpha blockers
Stroke: Clinical (To be retired)
Seizures: Clinical (To be retired)
Headaches: Clinical (To be retired)
Traumatic brain injury: Clinical (To be retired)
Neck trauma: Clinical (To be retired)
Lower back pain: Clinical (To be retired)
Spinal cord disorders: Pathology review
Anticonvulsants and anxiolytics: Barbiturates
Anticonvulsants and anxiolytics: Benzodiazepines
Nonbenzodiazepine anticonvulsants
Migraine medications
Osmotic diuretics
Antiplatelet medications
Thrombolytics
Opioid agonists, mixed agonist-antagonists and partial agonists
Opioid antagonists
Asthma: Clinical (To be retired)
Chronic obstructive pulmonary disease (COPD): Clinical (To be retired)
Venous thromboembolism: Clinical (To be retired)
Acute respiratory distress syndrome: Clinical (To be retired)
Pleural effusion: Clinical (To be retired)
Pneumothorax: Clinical (To be retired)
Chest trauma: Clinical (To be retired)
Bronchodilators: Beta 2-agonists and muscarinic antagonists
Pulmonary corticosteroids and mast cell inhibitors
Joint pain: Clinical (To be retired)
Anatomy clinical correlates: Clavicle and shoulder
Anatomy clinical correlates: Axilla
Anatomy clinical correlates: Arm, elbow and forearm
Anatomy clinical correlates: Wrist and hand
Anatomy clinical correlates: Median, ulnar and radial nerves
Anatomy clinical correlates: Bones, joints and muscles of the back
Anatomy clinical correlates: Hip, gluteal region and thigh
Anatomy clinical correlates: Knee
Anatomy clinical correlates: Leg and ankle
Anatomy clinical correlates: Foot
Acetaminophen (Paracetamol)
Non-steroidal anti-inflammatory drugs
Glucocorticoids
Opioid agonists, mixed agonist-antagonists and partial agonists
Antigout medications
Calcium channel blockers
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Ursula Florjanczyk, MScBMC
Victoria S. Recalde, MD
Evan Debevec-McKenney
Calcium entry blockers, or calcium channel blockers - CCBs for short - are vasodilators, or medications that promote dilation of blood vessels. These medications are mainly used to treat hypertension, or high blood pressure, and angina pectoris, which is a pain caused by reduced blood flow to the heart muscle. Now, by definition, blood pressure is the force that blood exerts on the walls of blood vessels and it’s basically what keeps blood flowing and perfusing tissues to deliver oxygen and nutrients. Hypertension happens when this pressure is higher than it should be. In most cases, the cause is unknown.
But basically, we can do a number of things to help lower the blood pressure. First, we can decrease the heart rate or the myocardial contractility, so the heart pumps less blood into the blood vessels. In other words, diminish the amount of blood that exerts force upon the same area. Or, we can vasodilate the peripheral blood vessels, which increases the area for the same amount of liquid that exerts force. Angina, on the other hand, is a type of chest pain caused by insufficient oxygen supply to the myocardium to meet its demand. Generally, the underlying cause is the presence of atheromatous plaques in the coronary arteries which decreases the blood flow to the heart. So, to help diminish the symptoms, it’s important to decrease the oxygen demand of the heart, again by decreasing heart rate or myocardial contractility; and increasing the oxygen supply by vasodilating the coronary arteries.
Now, let’s look at how calcium channels affect heart function. First off, the heart rate depends on the rate that the pacemaker cells in the sinus and atrioventricular node generate action potentials. These action potentials start automatically when sodium channels slowly let in a stream of sodium ions, which causes the membrane potential of the pacemaker cells to become more positive. When this reaches the threshold membrane potential, it’s the cue for voltage-gated calcium channels to open, allowing a large influx of calcium ions, which depolarizes it further. Then, these calcium channels close and potassium channels open to let potassium out of the cell, so the membrane potential goes back down, or repolarizes. Now, each cycle of depolarization and repolarization represents a single heartbeat, so how fast this process repeats in one minute determines the heart rate.
Calcium channel blockers (CCBs) are a class of drugs that cause vasodilation, and are mainly used to treat high blood pressure and angina pectoris. CCBs block calcium flow into the smooth muscle cells of your blood vessels, resulting in vasodilation and reduced blood pressure. They also work on cardiac muscle cells to reduce contractility and abnormally increased heart rate.
CCBs are grouped into two main types; dihydropyridines and non-dihydropyridines. Dihydropyridines mainly cause vasodilation and so are used to treat hypertension and angina. Examples of dihydropyridines include amlodipine, nicardipine, and nifedipine). The non-dihydropyridines target the heart muscle cells and decrease the heart rate and contractility. They are usually used to treat tachyarrhythmias, but also angina, because by reducing the heart rate and contractility, they bring down cardiac demand. Examples of non-dihydropyridines include diltiazem and verapamil. CCBs are typically well-tolerated, but they can cause certain side effects, such as dizziness, lightheadedness, and swelling of the ankles or legs.
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