Diltiazem

Last updated

Diltiazem
Diltiazem structure.svg
Diltiazem ball-and-stick.png
Clinical data
Pronunciation /dɪlˈtəzɛm/
Trade names Cardizem, others
AHFS/Drugs.com Monograph
MedlinePlus a684027
License data
Pregnancy
category
Routes of
administration
By mouth, intravenous
Drug class Nondihydropyridine calcium channel blocker
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability 40%
Metabolism Liver
Elimination half-life 3–4.5 hours
Excretion Kidney
Bile duct
Identifiers
  • cis-(+)-[2-(2-Dimethylaminoethyl)-5-(4-methoxyphenyl)-3-oxo-6-thia-2-azabicyclo[5.4.0]undeca-7,9,11-trien-4-yl]ethanoate
CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
PDB ligand
CompTox Dashboard (EPA)
ECHA InfoCard 100.050.707 OOjs UI icon edit-ltr-progressive.svg
Chemical and physical data
Formula C22H26N2O4S
Molar mass 414.52 g·mol−1
3D model (JSmol)
  • O=C2N(c3c(S[C@@H](c1ccc(OC)cc1)[C@H]2OC(=O)C)cccc3)CCN(C)C
  • InChI=1S/C22H26N2O4S/c1-15(25)28-20-21(16-9-11-17(27-4)12-10-16)29-19-8-6-5-7-18(19)24(22(20)26)14-13-23(2)3/h5-12,20-21H,13-14H2,1-4H3/t20-,21+/m1/s1 Yes check.svgY
  • Key:HSUGRBWQSSZJOP-RTWAWAEBSA-N Yes check.svgY
   (verify)

Diltiazem, sold under the brand name Cardizem among others, is a nondihydropyridine calcium channel blocker medication used to treat high blood pressure, angina, and certain heart arrhythmias. [9] It may also be used in hyperthyroidism if beta blockers cannot be used. [9] It is taken by mouth or given by injection into a vein. [9] When given by injection, effects typically begin within a few minutes and last a few hours. [9]

Contents

Common side effects include swelling, dizziness, headaches, and low blood pressure. [9] Other severe side effects include an overly slow heart beat, heart failure, liver problems, and allergic reactions. [9] Use is not recommended during pregnancy. [9] It is unclear if use when breastfeeding is safe. [1]

Diltiazem works by relaxing the smooth muscle in the walls of arteries, resulting in them opening and allowing blood to flow more easily. [9] Additionally, it acts on the heart to prolong the period until it can beat again. [10] It does this by blocking the entry of calcium into the cells of the heart and blood vessels. [11] It is a class IV antiarrhythmic. [12]

Diltiazem was approved for medical use in the United States in 1982. [9] It is available as a generic medication. [9] In 2022, it was the 100th most commonly prescribed medication in the United States, with more than 6 million prescriptions. [13] [14] An extended release formulation is also available. [5] [6] [9]

Medical uses

Diltiazem is indicated for:

For supraventricular tachycardias (PSVT), diltiazem appears to be as effective as verapamil in treating re-entrant supraventricular tachycardia. [17]

Atrial fibrillation [18] or atrial flutter is another indication. The initial bolus should be 0.25 mg/kg, intravenous (IV).

Because of its vasodilatory effects, diltiazem is useful for treating hypertension. Calcium channel blockers are well tolerated, and especially effective in treating low-renin hypertension. [19]

It is also used as topical application for anal fissures because it promotes healing due to its vasodilatory property. [20]

Contraindications and precautions

Diltiazem is relatively contraindicated in the presence of sick sinus syndrome, atrioventricular node conduction disturbances, bradycardia, impaired left ventricle function, peripheral artery occlusive disease, and chronic obstructive pulmonary disease.

Side effects

A reflex sympathetic response, caused by the peripheral dilation of vessels and the resulting drop in blood pressure, works to counteract the negative inotropic, chronotropic and dromotropic effects of diltiazem. Undesirable effects include hypotension, bradycardia, dizziness, flushing, fatigue, headaches and edema. [21] Rare side effects are congestive heart failure, myocardial infarction, and hepatotoxicity. [22]


Drug interactions

Because of its inhibition of hepatic cytochromes CYP3A4, CYP2C9 and CYP2D6, there are a number of drug interactions. [23] Some of the more important interactions are listed below.

Beta-blockers

Intravenous diltiazem should be used with caution with beta-blockers because, while the combination is most potent at reducing heart rate, there are rare instances of dysrhythmia and AV node block. [24]

Quinidine

Quinidine should not be used concurrently with calcium channel blockers because of reduced clearance of both drugs and potential pharmacodynamic effects at the SA and AV nodes. [25]

Fentanyl

Concurrent use of fentanyl with diltiazem, or any other CYP3A4 inhibitors, as these medications decrease the breakdown of fentanyl and thus increase its effects. [26]

Mechanism of action

180 mg Cardizem capsule 000197lg cardizem 180mg.jpg
180 mg Cardizem capsule

Diltiazem, also known as (2S,3S)-3-acetoxy-5-[2-(dimethylamino)ethyl]-2,3-dihydro-2-(4-methoxyphenyl)-1,5-benzothiazepin-4(5H)-one hydrochlorid has a vasodilating activity attributed to the (2S,3S)-isomer. [27] Diltiazem is a potent vasodilator, increasing blood flow and variably decreasing the heart rate via strong depression of A-V node conduction. It binds to the alpha-1 subunit of L-type calcium channels in a fashion somewhat similar to verapamil, another nondihydropyridine (non-DHP) calcium channel blocker. [28] Chemically, it is based upon a 1,4-thiazepine ring, making it a benzothiazepine-type calcium channel blocker.

It is a potent and mild vasodilator of coronary and peripheral vessels, respectively, [29] which reduces peripheral resistance and afterload, though not as potent as the dihydropyridine (DHP) calcium channel blockers. This results in minimal reflexive sympathetic changes.[ citation needed ]

Diltiazem has negative inotropic, chronotropic, and dromotropic effects. This means diltiazem causes a decrease in heart muscle contractility – how strong the beat is, lowering of heart rate – due to slowing of the sinoatrial node, and a slowing of conduction through the atrioventricular node – increasing the time needed for each beat. Each of these effects results in reduced oxygen consumption by the heart, reducing angina, typically unstable angina, symptoms. These effects also reduce blood pressure by causing less blood to be pumped out.

Research

Diltiazem is prescribed off-label by doctors in the US for prophylaxis of cluster headaches. Some research on diltiazem and other calcium channel antagonists in the treatment and prophylaxis of migraine is ongoing. [15] [30] [31] [32] [33] [34] [35] [ needs update ]

Recent research[ when? ] has shown diltiazem may reduce cocaine cravings in drug-addicted rats. [36] This is believed to be due to the effects of calcium blockers on dopaminergic and glutamatergic signaling in the brain. [37] Diltiazem also enhances the analgesic effect of morphine in animal tests, without increasing respiratory depression, [38] and reduces the development of tolerance. [39]

Diltiazem is also being used in the treatment of anal fissures. It can be taken orally or applied topically with increased effectiveness. [40] When applied topically, it is made into a cream form using either petrolatum or Phlojel. Phlojel absorbs the diltiazem into the problem area better than the petrolatum base. It has good short-term success rates. [41] [42]

Related Research Articles

An antianginal is a drug used in the treatment of angina pectoris, a symptom of ischaemic heart disease.

<span class="mw-page-title-main">Beta blocker</span> Medications for abnormal heart rhythms

Beta blockers, also spelled β-blockers, are a class of medications that are predominantly used to manage abnormal heart rhythms (arrhythmia), and to protect the heart from a second heart attack after a first heart attack. They are also widely used to treat high blood pressure, although they are no longer the first choice for initial treatment of most patients.

Calcium channel blockers (CCB), calcium channel antagonists or calcium antagonists are a group of medications that disrupt the movement of calcium through calcium channels. Calcium channel blockers are used as antihypertensive drugs, i.e., as medications to decrease blood pressure in patients with hypertension. CCBs are particularly effective against large vessel stiffness, one of the common causes of elevated systolic blood pressure in elderly patients. Calcium channel blockers are also frequently used to alter heart rate, to prevent peripheral and cerebral vasospasm, and to reduce chest pain caused by angina pectoris.

<span class="mw-page-title-main">Verapamil</span> Calcium channel blocker medication

Verapamil, sold under various trade names, is a calcium channel blocker medication used for the treatment of high blood pressure, angina, and supraventricular tachycardia. It may also be used for the prevention of migraines and cluster headaches. It is given by mouth or by injection into a vein.

Antiarrhythmic agents, also known as cardiac dysrhythmia medications, are a class of drugs that are used to suppress abnormally fast rhythms (tachycardias), such as atrial fibrillation, supraventricular tachycardia and ventricular tachycardia.

<span class="mw-page-title-main">Amlodipine</span> Medication against high blood pressure

Amlodipine, sold under the brand name Norvasc among others, is a calcium channel blocker medication used to treat high blood pressure, coronary artery disease (CAD) and variant angina. It is taken orally.

<span class="mw-page-title-main">Amiodarone</span> Antiarrhythmic medication used for various types of irregular heartbeats

Amiodarone is an antiarrhythmic medication used to treat and prevent a number of types of cardiac dysrhythmias. This includes ventricular tachycardia, ventricular fibrillation, and wide complex tachycardia, atrial fibrillation, and paroxysmal supraventricular tachycardia. Evidence in cardiac arrest, however, is poor. It can be given by mouth, intravenously, or intraosseously. When used by mouth, it can take a few weeks for effects to begin.

<span class="mw-page-title-main">Nifedipine</span> Calcium channel blocker medication

Nifedipine, sold under the brand name Procardia among others, is a calcium channel blocker medication used to manage angina, high blood pressure, Raynaud's phenomenon, and premature labor. It is one of the treatments of choice for Prinzmetal angina. It may be used to treat severe high blood pressure in pregnancy. Its use in preterm labor may allow more time for steroids to improve the baby's lung function and provide time for transfer of the mother to a well qualified medical facility before delivery. It is a calcium channel blocker of the dihydropyridine type. Nifedipine is taken by mouth and comes in fast- and slow-release formulations.

<span class="mw-page-title-main">Sotalol</span> Medication

Sotalol, sold under the brand name Betapace among others, is a medication used to treat and prevent abnormal heart rhythms. Evidence does not support a decreased risk of death with long term use. It is taken by mouth or given by injection into a vein.

<span class="mw-page-title-main">Nadolol</span> Non-selective beta blocker used in the treatment of high blood pressure and chest pain

Nadolol, sold under the brand name Corgard among others, is a medication used to treat high blood pressure, heart pain, atrial fibrillation, and some inherited arrhythmic syndromes. It has also been used to prevent migraine headaches and complications of cirrhosis. It is taken orally.

Vasospasm refers to a condition in which an arterial spasm leads to vasoconstriction. This can lead to tissue ischemia and tissue death (necrosis). Cerebral vasospasm may arise in the context of subarachnoid hemorrhage. Symptomatic vasospasm or delayed cerebral ischemia is a major contributor to post-operative stroke and death especially after aneurysmal subarachnoid hemorrhage. Vasospasm typically appears 4 to 10 days after subarachnoid hemorrhage.

<span class="mw-page-title-main">Nebivolol</span> Chemical compound

Nebivolol is a beta blocker used to treat high blood pressure and heart failure. As with other β-blockers, it is generally a less preferred treatment for high blood pressure. It may be used by itself or with other blood pressure medication. It is taken by mouth.

<span class="mw-page-title-main">Lercanidipine</span> Antihypertensive drug of the calcium channel blocker class

Lercanidipine is an antihypertensive drug. It belongs to the dihydropyridine class of calcium channel blockers, which work by relaxing and opening the blood vessels allowing the blood to circulate more freely around the body. This lowers the blood pressure and allows the heart to work more efficiently.

<span class="mw-page-title-main">Nisoldipine</span> Antihypertensive drug of the calcium channel blocker class

Nisoldipine is a pharmaceutical drug used for the treatment of chronic angina pectoris and hypertension. It is a calcium channel blocker of the dihydropyridine class. It is sold in the United States under the proprietary name Sular. Nisoldipine has tropism for cardiac blood vessels.

The term dromotropic derives from the Greek word δρόμος drómos, meaning "running", a course, a race. A dromotropic agent is one which affects the conduction speed in the AV node, and subsequently the rate of electrical impulses in the heart.

<span class="mw-page-title-main">Ranolazine</span> Drug used to treat angina

Ranolazine, sold under the brand name Ranexa among others, is a medication used to treat heart related chest pain. Typically it is used together with other medications when those are insufficient. Therapeutic benefits appear smaller in females than males. It is taken by mouth.

<span class="mw-page-title-main">Pilsicainide</span> Chemical compound

Pilsicainide (INN) is an antiarrhythmic agent. It is marketed in Japan as サンリズム (Sunrythm). It was developed by Suntory Holdings Limited and first released in 1991. The JAN applies to the hydrochloride salt, pilsicainide hydrochloride.

<span class="mw-page-title-main">Efonidipine</span> Antihypertensive drug of the calcium channel blocker class

Efonidipine (INN) is a dihydropyridine calcium channel blocker marketed by Shionogi & Co. of Japan. It was launched in 1995, under the brand name Landel (ランデル). The drug blocks both T-type and L-type calcium channels. Drug Controller General of India (DCGI) has approved the use of efonidipine in India. It is launched under the brand name "Efnocar".

<span class="mw-page-title-main">Landiolol</span> Chemical compound

Landiolol (INN) is an ultra short-acting, β1-superselective intravenous adrenergic antagonist, which decreases the heart rate effectively with less negative effect on blood pressure or myocardial contractility. In comparison to other beta blockers, landiolol has the shortest elimination half-life, ultra-rapid onset of effect, and predictable effectiveness with inactive metabolites. The pure S-enantiomer structure of landiolol is believed to develop less hypotensive side effects in comparison to other β-blockers. This has a positive impact on the treatment of patients when reduction of heart rate without decrease in arterial blood pressure is desired. It is used as landiolol hydrochloride.

<span class="mw-page-title-main">AH-1058</span> Chemical compound

AH-1058 is a lipophilic antiarrhythmic calcium channel blocker synthesized by the Pharmaceutical Research Laboratories of Ajinomoto Co., Inc in Kawasaki, Japan. It is derived from cyproheptadine, a compound with known antiserotonic, antihistaminic and calcium channel blocking properties. The IUPAC name of AH-1058 is: 4-(5H-dibenzo[a,d]cyclohepten-5-ylidene)-1-[E-3-(3-methoxy-2-nitro) phenyl-2-propenyl]piperidine hydrochloride.

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