Related Concept Videos

Antiarrhythmic Drugs: Class IV Agents as Calcium Channel Blockers01:20

Antiarrhythmic Drugs: Class IV Agents as Calcium Channel Blockers

Class IV antiarrhythmic drugs, such as verapamil and diltiazem, block calcium channels. They primarily affect the heart, slowing the conduction in calcium-dependent tissues like the SA and AV nodes. These drugs manage reentrant supraventricular tachycardia (SVT) and reduce ventricular rate in atrial flutter/fibrillation.
Verapamil, a calcium channel blocker, inhibits calcium movement across myocardial cell membranes and vascular smooth muscle. This results in the dilation of coronary and...
Antianginal Drugs: Calcium Channel Blockers and Ranolazine01:25

Antianginal Drugs: Calcium Channel Blockers and Ranolazine

Angina pectoris, a primary symptom of ischemic heart disease, requires careful pharmacological interventions. In this context, calcium channel blockers (CCBs) and ranolazine have emerged as crucial pharmacotherapeutic agents, providing deep insights into the complexities of angina management.
CCBs, a diverse class that includes dihydropyridines (nifedipine) and diphenylalkylamines (verapamil and diltiazem), exert their effect by blocking calcium channels in cardiac and smooth muscle cells. This...
Treatment for Pulmonary Arterial Hypertension: Receptor Tyrosine Kinase Inhibitors and Calcium Channel Blockers01:26

Treatment for Pulmonary Arterial Hypertension: Receptor Tyrosine Kinase Inhibitors and Calcium Channel Blockers

Receptor tyrosine kinase inhibitors (TKIs) and calcium channel blockers (CCBs) are two critical categories of drugs employed in the treatment of pulmonary artery hypertension (PAH). PAH is a disease that causes high blood pressure in the pulmonary arteries, resulting in chest pain, fatigue, and shortness of breath.
TKIs, such as imatinib (Gleevec), are particularly effective in tackling the growth and mitogenic factors that become upregulated in PAH patients. These factors contribute to the...
Drugs for Treatment of Constipation-Predominant IBS01:21

Drugs for Treatment of Constipation-Predominant IBS

Pharmacological therapies for IBS-C are designed to alleviate abdominal discomfort and enhance bowel function. In patients with IBS-C, fiber supplements may help soften stools and decrease straining, but may also lead to increased gas production and bloating. Osmotic laxatives like milk of magnesia are frequently used to soften stools and increase stool frequency in IBS-C patients. In addition, two drugs approved for use in severe IBS-C adult cases are linaclotide (Linzess) and lubiprostone...
Effect of Hepatic Disease on Pharmacokinetics: Dose Adjustments Due to Hepatic Impairment01:08

Effect of Hepatic Disease on Pharmacokinetics: Dose Adjustments Due to Hepatic Impairment

Hepatic impairment, characterized by decreased liver function, does not uniformly mandate adjustments in drug dosage. Whether dosage modifications are necessary depends on various factors related to the drug's metabolism and elimination pathways. If a drug is primarily excreted via the kidneys and bypasses significant hepatic processing, if it undergoes minimal metabolic transformation in the liver, or if it is volatile and primarily expelled through the lungs, dose adjustments may not be...
Drug toxicity: Drug–Drug Interaction01:30

Drug toxicity: Drug–Drug Interaction

Drug–drug interactions can precipitate toxicity through multiple mechanisms. Absorption interactions alter how drugs enter the body, exemplified when ranitidine increases the absorption of basic drugs, while cholestyramine decreases the levels of propranolol. Protein binding interactions occur when drugs share the same binding sites on plasma proteins. Drugs like aspirin and warfarin, when bound in excess, can lead to increased free drug concentrations, enhancing the potential for...