NationMaster - Encyclopedia: Antiarrhythmic agent

Antiarrhythmic agents are a group of pharmaceuticals that are used to suppress fast rhythms of the heart (cardiac arrhythmias), such as atrial fibrillation, atrial flutter, ventricular tachycardia, and ventricular fibrillation. Pharmacology (in Greek: pharmacon is drug, and logos is science) is the study of how chemical substances interfere with living systems. ... The heart and lungs, from an older edition of Grays Anatomy. ... A cardiac arrhythmia, also called cardiac dysrhythmia, is a disturbance in the regular rhythm of the heartbeat. ... Atrial fibrillation (AF or afib) is an abnormal heart rhythm (cardiac arrhythmia) which involves the two small, upper heart chambers (the atria). ... Atrial flutter is an abnormal fast heart rhythm that occurs in the atria of the heart. ... Ventricular tachycardia (V-tach or VT) is a fast rhythm that originates in one of the ventricles of the heart. ... Ventricular fibrillation (V-fib or VF) is a cardiac condition which consists of a lack of coordination of the contraction of the muscle tissue of the large chambers of the heart that eventually leads to the heart stopping altogether. ...

While the use of antiarrhythmic agents to suppress atrial arrhythmias (atrial fibrillation and atrial flutter) is still in practice, it is unclear whether suppression of atrial arrhythmias will prolong life.^[1]^[2]

In the past, it was believed that following myocardial infarction (heart attack), suppression of ventricular arrhythmias would prolong life. However large clinical trials found that suppression of these arrhythmias would paradoxically increase mortality,^[3]^[4] which may happen due to the proarrhythmic effect these drugs may have (CAST trial). Acute myocardial infarction (AMI or MI), more commonly known as a heart attack, is a disease state that occurs when the blood supply to a part of the heart is interrupted. ...

In individuals with atrial fibrillation, antiarrhythmics are still used to suppress arrhythmias. This is often done to relieve the symptoms that may be associated with the loss of the atrial component to ventricular filling (atrial kick) that is due to atrial fibrillation or flutter. Atrial fibrillation (AF or afib) is an abnormal heart rhythm (cardiac arrhythmia) which involves the two small, upper heart chambers (the atria). ... Atrial flutter is an abnormal fast heart rhythm that occurs in the atria of the heart. ...

In individuals with ventricular arrhythmias, antiarrhythmic agents are often still in use to suppress arrhythmias. In this case, the patient may have frequent arrhythmic events or be at high risk for ventricular arrhythmias. Antiarrhythmic agents may be considered the first-line therapy in the prevention of sudden death in certain forms of structural heart disease, and failure of these agents to suppress arrhythmias may lead to implantation of an implantable cardioverter-defibrillator (ICD). A cardiac arrest, also known as cardiorespiratory arrest, cardiopulmonary arrest or circulatory arrest, is the abrupt cessation of normal circulation of the blood due to failure of the heart to contract effectively during systole[1]. Arrested blood circulation prevents delivery of oxygen to all parts of the body. ... An implantable cardioverter-defibrillator (ICD), also known as an automated implantable cardioverter-defibrillator (AICD), is a device that is implanted under the skin of patients that are at risk of sudden cardiac death due to ventricular fibrillation. ...

The use of antiarrhythmic agents in this population may be in conjunction with an ICD. In this case, the ICD is used to prevent sudden death due to ventricular fibrillation, while the antiarrhythmic agent(s) are used to suppress ventricular tachyarrhythmias so that the ICD doesn't shock the patient frequently. A cardiac arrest, also known as cardiorespiratory arrest, cardiopulmonary arrest or circulatory arrest, is the abrupt cessation of normal circulation of the blood due to failure of the heart to contract effectively during systole[1]. Arrested blood circulation prevents delivery of oxygen to all parts of the body. ...

Many attempts have been made to classify antiarrhythmic agents. The problem arises from the fact that many of the antiarrhythmic agents have multiple modes of action, making any classification imprecise. Schematic of an action potential, drawn by User:Diberri in Adobe Illustrator. ... Schematic of an action potential, drawn by User:Diberri in Adobe Illustrator. ...

Vaughan Williams antiarrhythmic classification

The Vaughan Williams classification is one of the most widely used classification schemes for antiarrhythmic agents. This scheme classifies a drug based on the primary mechanism of its antiarrhythmic effect. However, its dependence on primary mechanism is one of the limitations of the VW classification, since many antiarrhythmic agents have multiple action mechanisms. Amiodarone, for example, has effects consistent with all of the first four classes. Another limitation is the lack of consideration within the VW classification system for the effects of drug metabolites. Procainamide—a class Ia agent whose metabolite N-acetyl procainamide (NAPA) has a class III action—is one such example. A historical limitation was that drugs such as digoxin and adenosine – important antiarrhythmic agents – had no place at all in the VW classification system. This has since been rectified by the inclusion of class V. Amiodarone belongs to a class of drugs called Vaughan-Williams Class III antiarrhythmic agent. ... Procainamide (trade name Pronestyl®) is a pharmaceutical antiarrhythmic agent used for the medical treatment of cardiac arrhythmias, classified by the Vaughan Williams classification system as class Ia. ... N-Acetylprocainamide (NAPA) (or acecainide) is the N-acetylated metabolite of procainamide. ... Digoxin (INN) (IPA: ) is a purified cardiac glycoside extracted from the foxglove plant, Digitalis lanata. ... Adenosine is a nucleoside comprised of adenine attached to a ribose (ribofuranose) moiety via a Î²-N9-glycosidic bond. ...

There are five main classes in the Vaughan Williams classification of antiarrhythmic agents:

General Name, Symbol, Number sodium, Na, 11 Chemical series alkali metals Group, Period, Block 1, 3, s Appearance silvery white Standard atomic weight 22. ... Grays FIG. 838â€“ The right sympathetic chain and its connections with the thoracic, abdominal, and pelvic plexuses. ... Beta blockers or beta-adrenergic blocking agents are a class of drugs used to treat a variety of cardiovascular conditions and some other diseases. ... General Name, Symbol, Number potassium, K, 19 Chemical series alkali metals Group, Period, Block 1, 4, s Appearance silvery white Standard atomic weight 39. ... The atrioventricular node (abbreviated AV node) is the tissue between the atria and the ventricles of the heart, which conducts the normal electrical impulse from the atria to the ventricles. ...

Class I agents

The class I antiarrhythmic agents interfere with the sodium (Na⁺) channel. Class I agents are grouped by what effect they have on the Na⁺ channel, and what effect they have on cardiac action potentials. General Name, Symbol, Number sodium, Na, 11 Chemical series alkali metals Group, Period, Block 1, 3, s Appearance silvery white Standard atomic weight 22. ... A. A schematic view of an idealized action potential illustrates its various phases as the action potential passes a point on a cell membrane. ...

Class Ia agents

Class Ia agents block the fast sodium channel. Blocking this channel depresses the phase 0 depolarization (reduces V_max), which prolongs the action potential duration by slowing conduction. Agents in this class also cause decreased conductivity and increased refractoriness. Image File history File links Action of Class Ia agents on the cardiac action potential File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Action of Class Ia agents on the cardiac action potential File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... It has been suggested that this article or section be merged into Refractory period. ...

Indications for Class Ia agents are supraventricular tachycardia, ventricular tachycardia, symptomatic ventricular premature beats, and prevention of ventricular fibrillation. A supraventricular tachycardia (SVT) is a rapid rhythm of the heart in which the origin of the electrical signal is either the atria or the AV node. ... Ventricular tachycardia (V-tach or VT) is a fast rhythm that originates in one of the ventricles of the heart. ... Ventricular fibrillation (V-fib or VF) is a cardiac condition which consists of a lack of coordination of the contraction of the muscle tissue of the large chambers of the heart that eventually leads to the heart stopping altogether. ...

Procainamide can be used in the treatment of atrial fibrillation in the setting of Wolff-Parkinson-White syndrome, and in the treatment of wide complex hemodynamically stable tachycardias. Atrial fibrillation (AF or afib) is an abnormal heart rhythm (cardiac arrhythmia) which involves the two small, upper heart chambers (the atria). ... Wolff-Parkinson-White syndrome (WPW) is a syndrome of pre-excitation of the ventricles of the heart due to an accessory pathway known as the Bundle of Kent. ... This article or section does not cite any references or sources. ...

While procainamide and quinidine may be used in the conversion of atrial fibrillation to normal sinus rhythm, they should only be used in conjunction with an AV node blocking agent (ie: digoxin, verapamil, or a beta blocker), because procainamide and quinidine can increase the conduction through the AV node and may cause 1:1 conduction of atrial fibrillation, causing an increase in the ventricular rate. The atrioventricular node (abbreviated AV node) is the tissue between the atria and the ventricles of the heart, which conducts the normal electrical impulse from the atria to the ventricles. ... Digoxin (INN) (IPA: ) is a purified cardiac glycoside extracted from the foxglove plant, Digitalis lanata. ... Verapamil (brand names: IsoptinÂ®, VerelanÂ®, CalanÂ®) is a medical drug that acts as an L-type calcium channel blocker. ... Beta blockers or beta-adrenergic blocking agents are a class of drugs used to treat a variety of cardiovascular conditions and some other diseases. ...

Class Ia agents include quinidine, procainamide and disopyramide. Quinidine is a pharmaceutical agent that acts as a class I antiarrhythmic agent in the heart. ... Procainamide (trade name Pronestyl®) is a pharmaceutical antiarrhythmic agent used for the medical treatment of cardiac arrhythmias, classified by the Vaughan Williams classification system as class Ia. ... Disopyramide (INN, trade names NorpaceÂ® and RythmodanÂ®) is an antiarrhythmic medication. ...

Class Ib agents

Class Ib antiarrhythmic agents are sodium channel blockers. Class Ib agents have fast onset and offset kinetics, meaning that they have little or no effect at slower heart rates, and more effects at faster heart rates. Class Ib agents shorten the action potential duration and reduce refractoriness. These agents will decrease V_max in partially depolarized cells with fast response action potentials. They either do not change the action potential duration, or they may decrease the action potential duration. Image File history File links Action of class Ib antiarrhythmic agents on the action potential File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Action of class Ib antiarrhythmic agents on the action potential File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...

Class Ib agents are indicated for the treatment of ventricular tachycardia and symptomatic premature ventricular beats, and prevention of ventricular fibrillation.

Class Ib agents include lidocaine, mexiletine, tocainide, and phenytoin. Lidocaine (INN) (IPA: ) or lignocaine (former BAN) (IPA: ) is a common local anesthetic and antiarrhythmic drug. ... Mexiletine (INN, sold under the trade name MexitilÂ®) belongs to the Class IB anti-arrhythmic group of medicines. ... Tocainide is a class Ib antiarrhythmic agent. ... Phenytoin sodium (marketed as DilantinÂ® in the USA and as EpanutinÂ® in the UK, by Parke-Davis, now part of Pfizer) is a commonly used antiepileptic. ...

Class Ic agents

Class Ic antiarrhythmic agents markedly depress the phase 0 depolarization (decreasing V_max). They decrease conductivity, but have a minimal effect on the action potential duration. Of the sodium channel blocking antiarrhythmic agents (the class I antiarrhythmic agents), the class Ic agents have the most potent sodium channel blocking effects. Image File history File links Effect of Class Ic antiarrhythmic agent on cardiac action potential File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Effect of Class Ic antiarrhythmic agent on cardiac action potential File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...

Class Ic agents are indicated for life-threatening ventricular tachycardia or ventricular fibrillation, and for the treatment of refractory supraventricular tachycardia (ie: atrial fibrillation). These agents are potentially pro-arrhythmic, especially in settings of structural heart disease (e.g. post-myocardial infarction), and are contraindicated in such settings. Atrial fibrillation (AF or afib) is an abnormal heart rhythm (cardiac arrhythmia) which involves the two small, upper heart chambers (the atria). ... Acute myocardial infarction (AMI or MI), more commonly known as a heart attack, is a disease state that occurs when the blood supply to a part of the heart is interrupted. ...

Class Ic agents include encainide, flecainide, moricizine, and propafenone. Encainide is a class Ic antiarrhythmic agent. ... Flecainide acetate is a class Ic antiarrhythmic agent used to prevent and treat tachyarrhythmias (abnormal fast rhythms of the heart). ... Moricizine is used to treat a blood disorder (high platelet count) which can cause blood clots to form. ... Propafenone ( proe-pa-FEEN-none)(brand name RythmolÂ®) is a class Ic anti-arrhythmic medication. ...

Class II agents

Class II agents are conventional beta blockers. They act by selectively blocking the effects of catecholamines at the β₁-adrenergic receptors, thereby decreasing sympathetic activity on the heart. These agents are particularly useful in the treatment of supraventricular tachycardias. They decrease conduction through the AV node. Beta blockers or beta-adrenergic blocking agents are a class of drugs used to treat a variety of cardiovascular conditions and some other diseases. ... tyrosine is the precursor of catecholamines epinephrine norepinephrine dopamine Synthesis Catecholamines are chemical compounds derived from the amino acid tyrosine containing catechol and amine groups. ... Epinephrine Norepinephrine The adrenergic receptors (or adrenoceptors) are a class of G protein-coupled receptors that are targets of the catecholamines. ... A supraventricular tachycardia (SVT) is a rapid rhythm of the heart in which the origin of the electrical signal is either the atria or the AV node. ... The atrioventricular node (abbreviated AV node) is the tissue between the atria and the ventricles of the heart, which conducts the normal electrical impulse from the atria to the ventricles. ...

Class II agents include esmolol, propranolol, and metoprolol. Esmolol (tradename Brevibloc®) is a cardioselective beta-blocker given by slow injection into the veins. ... Propranolol (INN) (IPA: ) is a non-selective beta blocker mainly used in the treatment of hypertension. ... â€œMinaxâ€ redirects here. ...

Class III agents

Class III agents predominantly block the potassium channels, thereby prolonging repolarization.^[5] Since these agents do not affect the sodium channel, conduction velocity is not decreased. The prolongation of the action potential duration and refractory period, combined with the maintenance of normal conduction velocity, prevent re-entrant arrhythmias. (The re-entrant rhythm is more likely to interact with tissue that has become refractory). Image File history File links Effect of class III antiarrhythmic agent on the cardiac action potential File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Effect of class III antiarrhythmic agent on the cardiac action potential File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...

Class III antiarrhythmic agents exhibit reverse use dependent prolongation of the action potential duration (Reverse use-dependence). This means that the refractoriness of the ventricular myocyte increases at lower heart rates. This increases the susceptibility of the myocardium to early after-depolarizations (EADs) at low heart rates. Antiarrhythmic agents that exhibit reverse use-dependence are more efficacious at preventing a tachyarrhythmia than converting someone into normal sinus rhythm. Because of the reverse use-dependence of class III agents, at low heart rates class III antiarrhythmic agents may paradoxically be more arrhythmogenic. Myocyte is the technical term for a muscle cell. ... Heart rate is a term used to describe the frequency of the cardiac cycle. ...

Amiodarone is indicated for the treatment of refractory VT or VF, particularly in the setting of acute ischemia. Amiodarone is also safe to use in individuals with cardiomyopathy and atrial fibrillation, to maintain normal sinus rhythm. Ventricular tachycardia (V-tach or VT) is a fast rhythm that originates in one of the ventricles of the heart. ... Ventricular fibrillation (V-fib or VF) is a cardiac condition which consists of a lack of coordination of the contraction of the muscle tissue of the large chambers of the heart that eventually leads to the heart stopping altogether. ... Atrial fibrillation (AF or afib) is an abnormal heart rhythm (cardiac arrhythmia) which involves the two small, upper heart chambers (the atria). ...

Sotalol is indicated for the treatment of atrial or ventricular tachyarrhythmias, and AV re-entrant arrhythmias. Ibutilide is the only antiarrhythmic agent currently approved by the Food and Drug Administration for acute conversion of atrial fibrillation to sinus rhythm. FDA logo The Food and Drug Administration (FDA) is an agency of the United States Department of Health and Human Services and is responsible for regulating food, dietary supplements, drugs, biological medical products, blood products, medical devices, radiation-emitting devices, veterinary products, and cosmetics in the United States. ... Atrial fibrillation (AF or afib) is an abnormal heart rhythm (cardiac arrhythmia) which involves the two small, upper heart chambers (the atria). ...

Class III agents include amiodarone, azimilide, bretylium, clofilium, dofetilide, tedisamil, ibutilide, sematilide, and sotalol. Amiodarone belongs to a class of drugs called Vaughan-Williams Class III antiarrhythmic agent. ... Azimilide an investigational class III anti-arrhythmic drug that blocks fast and slow components of the delayed rectifier cardiac potassium channels. ... Bretylium (also bretylium tosylate) blocks the release of noradrenaline from the peripheral sympathetic nervous system, and is used in emergency medicine, cardiology, & other specialties for the acute management of ventricular tachycardia & ventricular fibrilation. ... Dofetilide is a class III antiarrhythmic agent that is approved by the FDA for the maintenance of sinus rhythm in individuals prone to the formation of atrial fibrillation and flutter, and for the chemical cardioversion to sinus rhythm from atrial fibrillation and flutter. ... Ibutilide (ibutilide fumarate) is a class III antiarrhythmic agent. ... Sotalol is a drug used in individuals with rhythm disturbances (cardiac arrhythmias) of the heart. ...

Class IV agents

Class IV agents are slow calcium channel blockers. They decrease conduction through the AV node, and shorten phase two (the plateau) of the cardiac action potential. They thus reduce the contractility of the heart, so may be inappropriate in heart failure. However, in contrast to beta blockers, they allow the body to retain adrenergic control of heart rate and contractility. Calcium channel blockers are a class of drugs with effects on many excitable cells of the body, like the muscle of the heart, smooth muscles of the vessels or neuron cells. ... The atrioventricular node (abbreviated AV node) is the tissue between the atria and the ventricles of the heart, which conducts the normal electrical impulse from the atria to the ventricles. ...

Class IV agents include verapamil and diltiazem. Verapamil (brand names: IsoptinÂ®, VerelanÂ®, CalanÂ®) is a medical drug that acts as an L-type calcium channel blocker. ... Diltiazem is a member of the group of drugs known as Benzothiapines , which are a class of calcium channel blockers, used in the treatment of hypertension, angina pectoris, and some types of arrhythmia. ...

Class V agents

Class V agents include digoxin and adenosine. Digoxin increases vagal activity via its central action on the central nervous system, thus decreasing the conduction of electrical impulses through the AV node Digoxin (INN) (IPA: ) is a purified cardiac glycoside extracted from the foxglove plant, Digitalis lanata. ... Adenosine is a nucleoside comprised of adenine attached to a ribose (ribofuranose) moiety via a Î²-N9-glycosidic bond. ...

Trials

The Cardiac Arrhythmia Suppression Trial^[6] was a medical study that demonstrated that some class 1 anti-arrhythemic drugs were not helpful to people suffering from ventricular premature depolarization. Specifically, for populations of recent heart attack survivors, the study observed lower mortality in a control population than in populations treated with encainide, flecainide or moricizine (all class 1c drugs). In the heart, a ventricle is a chamber which collects blood from an atrium (another heart chamber) and pumps it out of the heart. ...

Mnemonics

Mnemonic for Class I-IV agents: SoBe PoCa (SOBE as in South Beach or the drink, POCA as in Polka)

Sodium channel blockers, Beta blockers, Potassium channel blockers, Calcium channel blockers

See also

A. A schematic view of an idealized action potential illustrates its various phases as the action potential passes a point on a cell membrane. ... The cardiac action potential is a specialized action potential in the heart, with unique properties necessary for function of the electrical conduction system of the heart. ... â€œQRSâ€ redirects here. ...

References

Categories: Antiarrhythmic agents | Cardiac electrophysiology A section of the Anatomical Therapeutic Chemical Classification System. ... Ajmaline is a class Ia antiarrhythmic agent. ... Disopyramide (INN, trade names NorpaceÂ® and RythmodanÂ®) is an antiarrhythmic medication. ... Prajmaline is a class 1a antiarrhythmic agent. ... Procainamide (trade name Pronestyl®) is a pharmaceutical antiarrhythmic agent used for the medical treatment of cardiac arrhythmias, classified by the Vaughan Williams classification system as class Ia. ... Quinidine is a pharmaceutical agent that acts as a class I antiarrhythmic agent in the heart. ... Sparteine is a class 1a antiarrhythmic agent. ... Aprindine is a class 1b antiarrhythmic agent. ... Lidocaine (INN) (IPA: ) or lignocaine (former BAN) (IPA: ) is a common local anesthetic and antiarrhythmic drug. ... Mexiletine (INN, sold under the trade name MexitilÂ®) belongs to the Class IB anti-arrhythmic group of medicines. ... Tocainide is a class Ib antiarrhythmic agent. ... Encainide is a class Ic antiarrhythmic agent. ... Flecainide acetate is a class Ic antiarrhythmic agent used to prevent and treat tachyarrhythmias (abnormal fast rhythms of the heart). ... Lorcainide is a class 1c antiarrhythmic agent. ... Moricizine is used to treat a blood disorder (high platelet count) which can cause blood clots to form. ... Propafenone ( proe-pa-FEEN-none)(brand name RythmolÂ®) is a class Ic anti-arrhythmic medication. ... Propranolol (INN) (IPA: ) is a non-selective beta blocker mainly used in the treatment of hypertension. ... â€œMinaxâ€ redirects here. ... Nadolol (Corgard) is a non-selective beta-blocker used in the treatment of high blood pressure and chest pain. ... Atenolol is a drug belonging to the group of beta blockers, a class of drugs used primarily in cardiovascular diseases. ... Acebutolol is a beta blocker. ... Pindolol is a beta blocker drug. ... Beta blockers or beta-adrenergic blocking agents are a class of drugs used to treat a variety of cardiovascular conditions and some other diseases. ... A section of the Anatomical Therapeutic Chemical Classification System. ... Amiodarone belongs to a class of drugs called Vaughan-Williams Class III antiarrhythmic agent. ... Bretylium (also bretylium tosylate) blocks the release of noradrenaline from the peripheral sympathetic nervous system, and is used in emergency medicine, cardiology, & other specialties for the acute management of ventricular tachycardia & ventricular fibrilation. ... Bunaftine is a class III antiarrhythmic agent. ... Dofetilide is a class III antiarrhythmic agent that is approved by the FDA for the maintenance of sinus rhythm in individuals prone to the formation of atrial fibrillation and flutter, and for the chemical cardioversion to sinus rhythm from atrial fibrillation and flutter. ... Ibutilide (ibutilide fumarate) is a class III antiarrhythmic agent. ... Sotalol is a drug used in individuals with rhythm disturbances (cardiac arrhythmias) of the heart. ... Verapamil (brand names: IsoptinÂ®, VerelanÂ®, CalanÂ®) is a medical drug that acts as an L-type calcium channel blocker. ... Diltiazem is a member of the group of drugs known as Benzothiapines , which are a class of calcium channel blockers, used in the treatment of hypertension, angina pectoris, and some types of arrhythmia. ... Calcium channel blockers are a class of drugs with effects on many excitable cells of the body, like the muscle of the heart, smooth muscles of the vessels or neuron cells. ... A section of the Anatomical Therapeutic Chemical Classification System. ... Adenosine is a nucleoside comprised of adenine attached to a ribose (ribofuranose) moiety via a Î²-N9-glycosidic bond. ... Atropine is a tropane alkaloid extracted from the deadly nightshade (Atropa belladonna) and other plants of the family Solanaceae. ... Digoxin (INN) (IPA: ) is a purified cardiac glycoside extracted from the foxglove plant, Digitalis lanata. ... Upper and Lower gastrointestinal tract The gastrointestinal tract (GI tract), also called the digestive tract, or the alimentary canal, is the system of organs within multicellular animals that takes in food, digests it to extract energy and nutrients, and expels the remaining waste. ... A section of the Anatomical Therapeutic Chemical Classification System. ... A bottle of antacid tablets An antacid is any substance, generally a base, which counteracts stomach acidity. ... An antiemetic is a drug that is effective against vomiting and nausea. ... An H2-receptor antagonist, often shortened to H2 antagonist, is a drug used to block the action of histamine on parietal cells in the stomach, decreasing acid production by these cells. ... Proton pump inhibitors (or PPIs) are a group of drugs whose main action is pronounced and long-lasting reduction of gastric acid production. ... Laxatives are foods, compounds, or drugs taken to induce bowel movements, most often taken to treat constipation. ... An antidiarrhoeal drug is the term used for any drug which provides symptomatic relief for diarrhoea. ... Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ... A section of the Anatomical Therapeutic Chemical Classification System. ... An anticoagulant is a substance that prevents coagulation; that is, it stops blood from clotting. ... An antiplatelet drug is a member of a class of pharmaceuticals that decreases platelet aggregation and inhibits thrombus formation. ... Thrombolytic drugs are used in medicine to dissolve blood clots in a procedure termed thrombolysis. ... The circulatory system or cardiovascular system is the organ system which circulates blood around the body of most animals. ... A section of the Anatomical Therapeutic Chemical Classification System. ... Antihypertensives are a class of drugs that are used in medicine and pharmacology to treat hypertension (high blood pressure). ... A diuretic (colloquially called a water pill) is any drug or herb that elevates the rate of bodily urine excretion (diuresis). ... Vasodilation is where blood vessels in the body become wider following the relaxation of the smooth muscle in the vessel wall. ... An antianginal is any drug used in the treatment of angina pectoris, a symptom of ischaemic heart disease. ... Beta blockers or beta-adrenergic blocking agents are a class of drugs used to treat a variety of cardiovascular conditions and some other diseases. ... Captopril, the first ACE inhibitor ACE inhibitors, or inhibitors of Angiotensin-Converting Enzyme, are a group of pharmaceuticals that are used primarily in treatment of hypertension and congestive heart failure, in most cases as the drugs of first choice. ... Hypolipidemic agents, or antihyperlipidemic agents, are a diverse group of pharmaceuticals that are used in the treatment of hyperlipidemias. ... Beyond overall skin structure, refer below to: See-also. ... A section of the Anatomical Therapeutic Chemical Classification System. ... Antipruritic is a drug which reduces pruritis, or itching. ... The reproductive system is the ensembles and interactions of organs and/or substances within an organism that strictly pertain to reproduction. ... A section of the Anatomical Therapeutic Chemical Classification System. ... Hormonal contraception refers to birth control methods that act on the hormonal system. ... Fertility medication may in a larger sense include any medication that enhances fertility, but in a specific sense consists of agents that stimulate follicle development of the ovary. ... Selective estrogen receptor modulators (SERMs) is a class of medication that acts on the estrogen receptor. ... This article or section does not cite any references or sources. ... A section of the Anatomical Therapeutic Chemical Classification System. ... In physiology, corticosteroids are a class of steroid hormones that are produced in the adrenal cortex. ... An anti-diabetic drug or oral hypoglycemic agent is used to treat diabetes mellitus. ... An infection is the detrimental colonization of a host organism by a foreign species. ... This page is a candidate to be moved to Wiktionary. ... A section of the Anatomical Therapeutic Chemical Classification System. ... A section of the Anatomical Therapeutic Chemical Classification System. ... Staphylococcus aureus - Antibiotics test plate. ... Antiviral drugs are a class of medication used specifically for treating viral infections. ... A vaccine is an antigenic preparation used to establish immunity to a disease. ... An antifungal drug is medication used to treat fungal infections such as athletes foot, ringworm, candidiasis (thrush), serious systemic infections such as cryptococcal meningitis, and others. ... Antiprotozoal agents (ATC code: ATC P01) is a class of pharmaceuticals used in treatment of protozoal infections. ... Anthelmintics (in the U.S., antihelminthics) are drugs that expel parasitic worms (helminthes) from the body or kill them. ... In medicine, malignant is a clinical term that means to be severe and become progressively worse, as in malignant hypertension. ... A scanning electron microscope image of a single neutrophil (yellow), engulfing anthrax bacteria (orange). ... A section of the Anatomical Therapeutic Chemical Classification System. ... Chemotherapy is the use of chemical substances to treat disease. ... For a list of immunosuppressive drugs, see the transplant rejection page. ... 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The Human Nervous System A human being coordinates its nervous system, the activity of the muscles, monitors the organs, constructs and also stops input from the senses, and initiates actions. ... A section of the Anatomical Therapeutic Chemical Classification System. ... Anesthesia or anaesthesia (see spelling differences) has traditionally meant the condition of having the perception of pain and other sensations blocked. ... An analgesic (colloquially known as a painkiller) is any member of the diverse group of drugs used to relieve pain (achieve analgesia). ... The anticonvulsants, sometimes also called antiepileptics, belong to a diverse group of pharmaceuticals used in prevention of the occurrence of epileptic seizures. ... A mood stabilizer is a psychiatric medication used to treat mood disorders characterized by rapid and unstable mood shifts. ... An anxiolytic is a drug prescribed for the treatment of symptoms of anxiety. ... 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Contents

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