Mephentermine

Last updated
Mephentermine
Mephentermine.svg
Clinical data
Other namesmethyl(2-methyl-1-phenylpropan-2-yl)amine
Routes of
administration
IM/IV
ATC code
Legal status
Legal status
Pharmacokinetic data
Metabolism Rapidly demethylated in the body followed by hydroxylation.
Excretion Via urine (as unchanged and metabolites); more rapid in acidic urine.
Identifiers
  • N,2-dimethyl-1-phenylpropan-2-amine
CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard 100.002.638 OOjs UI icon edit-ltr-progressive.svg
Chemical and physical data
Formula C11H17N
Molar mass 163.264 g·mol−1
3D model (JSmol)
  • N(C(Cc1ccccc1)(C)C)C
  • InChI=1S/C11H17N/c1-11(2,12-3)9-10-7-5-4-6-8-10/h4-8,12H,9H2,1-3H3 Yes check.svgY
  • Key:RXQCGGRTAILOIN-UHFFFAOYSA-N Yes check.svgY
 X mark.svgNYes check.svgY  (what is this?)    (verify)

Mephentermine (Wyamine, former brandname) is a cardiac stimulant.

Contents

It has been used as a treatment for low blood pressure. [1]

Mephentermine belongs to the class of adrenergic and dopaminergic cardiac stimulants excluding cardiac glycosides. Used in the treatment of heart failure.

Mechanism of action

Mephentermine appears to act by indirect stimulation of β-adrenergic receptors causing the release of norepinephrine from its storage sites. It has a positive inotropic effect on the myocardium. AV conduction and refractory period of AV node is shortened with an increase in ventricular conduction velocity. It dilates arteries and arterioles in the skeletal muscle and mesenteric vascular beds, leading to an increase in venous return.

Its onset is 5 to–15 minutes with intramuscular dosing, and immediate with intravenous dosing.

Its duration of action is four hours with intramuscular dosing and 30 minutes with intravenous dosing.

Indication and dosage

For maintenance of blood pressure in hypotensive states, the dose for adults is 30–45 mg as a single dose, repeated as necessary or followed by intravenous infusion of 0.1% mephentermine in 5% dextrose, with the rate and duration of administration depending on the patient's response.

For hypotension secondary to spinal anaesthesia in obstetric patients, the dose for adults is 15 mg as a single dose, repeated if needed. The maximum dose 30 mg.

Caution

Contraindications

Low blood pressure caused by phenothiazines, hypertension, and pheochromocytoma.

Special Precautions

Patients receiving monoamine oxidase inhibitors. For shock due to loss of blood or fluid, give fluid replacement therapy primarily, cardiovascular disease, hypertension, hyperthyroidism, chronic illnesses, lactation, pregnancy, skin dryness. headache.

Adverse Drug Reactions

The most common side effects are drowsiness, incoherence, hallucinations, convulsions, slow heart rate (reflex bradycardia). Fear, anxiety, restlessness, tremor, insomnia, confusion, irritability, and psychosis. Nausea, vomiting, reduced appetite, urinary retention, dyspnea, weakness, neck pain

Potentially fatal reactions are due to atrioventricular block, central nervous system stimulation, cerebral hemorrhage, pulmonary edema, and ventricular arrhythmias.

Drug Interactions

Mephentermine antagonizes effect of agents that lower blood pressure. Severe hypertension may occur with monoamine oxidase inhibitors and possibly tricyclic antidepressants. Additive vasoconstricting effects occur with ergot alkaloids, and oxytocin.

Potentially fatal drug interactions are the risk of abnormal heart rhythm in people undergoing anesthesia with cyclopropane and halothane.

Synthesis

Patent: Alternative Synthesis: Mephentermine synthesis.svg
Patent: Alternative Synthesis:

The Henry (Nitro-Aldol) reaction between Benzaldehyde [100-52-7] (1) and 2-Nitropropane [79-46-9] (2) gives 2-methyl-2-nitro-1-phenylpropan-1-ol [33687-74-0] (3). The nitro group is reduced with zinc in sulfuric acid giving 2-Phenyl-1,1-dimethylethanolamine [34405-42-0] (4). Imine formation by dehydration with benzaldehyde gives CID:12640087 (5). Alkylation with iodomethane led to CID:10058106 (6). Halogenation with thionyl chloride gave CID:129921490 (7). Lastly, a Rosenmund reduction completed the total synthesis of mephentermine (8).

According to JACS, phentermine was condensed with benzaldehyde to get the Schiff-base. This was then alkylated with methyl iodide to give mephentermine. [4]

Related Research Articles

<span class="mw-page-title-main">Beta blocker</span> Class of medications used to manage 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.

A decongestant, or nasal decongestant, is a type of pharmaceutical drug that is used to relieve nasal congestion in the upper respiratory tract. The active ingredient in most decongestants is either pseudoephedrine or phenylephrine. Intranasal corticosteroids can also be used as decongestants and antihistamines can be used to alleviate runny nose, nasal itch, and sneezing.

<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 (VT), ventricular fibrillation (VF), and wide complex tachycardia, as well as 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.

Atenolol is a beta blocker medication primarily used to treat high blood pressure and heart-associated chest pain. Atenolol, however, does not seem to improve mortality in those with high blood pressure. Other uses include the prevention of migraines and treatment of certain irregular heart beats. It is taken orally or by intravenous injection. It can also be used with other blood pressure medications.

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

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. It may also be used in hyperthyroidism if beta blockers cannot be used. It is taken by mouth or injection into a vein. When given by injection, effects typically begin within a few minutes and last a few hours.

<span class="mw-page-title-main">Loop diuretic</span> Diuretics that act at the ascending limb of the loop of Henle in the kidney

Loop diuretics are diuretics that act on the Na-K-Cl cotransporter along the thick ascending limb of the loop of Henle in nephrons of the kidneys. They are primarily used in medicine to treat hypertension and edema often due to congestive heart failure or chronic kidney disease. While thiazide diuretics are more effective in patients with normal kidney function, loop diuretics are more effective in patients with impaired kidney function.

<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.

<span class="mw-page-title-main">Sympathomimetic drug</span> Substance that mimics effects of catecholamines

Sympathomimetic drugs are stimulant compounds which mimic the effects of endogenous agonists of the sympathetic nervous system. Examples of sympathomimetic effects include increases in heart rate, force of cardiac contraction, and blood pressure. The primary endogenous agonists of the sympathetic nervous system are the catecholamines, which function as both neurotransmitters and hormones. Sympathomimetic drugs are used to treat cardiac arrest and low blood pressure, or even delay premature labor, among other things.

<span class="mw-page-title-main">Phenylephrine</span> Decongestant medication

Phenylephrine is a medication used as a decongestant for uncomplicated nasal congestion, used to dilate the pupil, used to increase blood pressure, and used to relieve hemorrhoids. It can be taken by mouth, given by injection into a vein or muscle, or applied to the skin.

<span class="mw-page-title-main">Bisoprolol</span> Beta-1 selective adrenenergic blocker medication used to treat cardiovascular diseases

Bisoprolol, sold under the brand name Zebeta among others, is a beta blocker medication used for heart diseases. This includes tachyarrhythmias, high blood pressure, chest pain from not enough blood flow to the heart, and heart failure. It is taken by mouth.

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

Bretylium (also bretylium tosylate) is an antiarrhythmic agent. It blocks the release of noradrenaline from nerve terminals. In effect, it decreases output from the peripheral sympathetic nervous system. It also acts by blocking K+ channels and is considered a class III antiarrhythmic. The dose is 5–10 mg/kg and side effects are high blood pressure followed by low blood pressure and ventricular ectopy.

<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">Dopexamine</span> Chemical compound

Dopexamine is a synthetic analogue of dopamine that is administered intravenously in hospitals to reduce exacerbations of heart failure and to treat heart failure following cardiac surgery. It is not used often, as more established drugs like epinephrine, dopamine, dobutamine, norepinephrine, and levosimendan work as well. It works by stimulating beta-2 adrenergic receptors and peripheral dopamine receptor D1 and dopamine receptor D2. It also inhibits the neuronal re-uptake of norepinephrine.

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

Benzoctamine is a drug that possesses sedative and anxiolytic properties. Marketed as Tacitin by Ciba-Geigy, it is different from most sedative drugs because in most clinical trials it does not produce respiratory depression, but actually stimulates the respiratory system. As a result, when compared to other sedative and anxiolytic drugs such as benzodiazepines like diazepam, it is a safer form of tranquilizing. However, when co-administered with other drugs that cause respiratory depression, like morphine, it can cause increased respiratory depression.

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

Etamivan is a respiratory stimulant drug related to nikethamide. It was mainly used in the treatment of barbiturate overdose and chronic obstructive pulmonary disease, but has now largely fallen into disuse.

Reflex bradycardia is a bradycardia in response to the baroreceptor reflex, one of the body's homeostatic mechanisms for preventing abnormal increases in blood pressure. In the presence of high mean arterial pressure, the baroreceptor reflex produces a reflex bradycardia as a method of decreasing blood pressure by decreasing cardiac output.

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

Clevidipine is a dihydropyridine calcium channel blocker indicated for the reduction of blood pressure when oral therapy is not feasible or not desirable. Clevidipine is used IV only and practitioners titrate this drug to lower blood pressure. It has a half-life of approximately one minute. It is rapidly inactivated by esterases.

<span class="mw-page-title-main">Alpha blocker</span> Class of pharmacological agents

Alpha-blockers, also known as α-blockers or α-adrenoreceptor antagonists, are a class of pharmacological agents that act as antagonists on α-adrenergic receptors (α-adrenoceptors).

<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. Landiolol was developed by modifying the chemical structure of esmolol to produce a compound with a higher rate of cardioselectivity and a greater potency without increasing its duration of action. It is sold as landiolol hydrochloride. Based on its positive benefit risk profile, landiolol has been granted the marketing authorization and introduced to the European markets under the brand names Rapibloc, Raploc, Runrapiq, Landibloc mid 2016. Landiolol is available in Japan under the brand names Onoact (50 mg) and Corbeta.

<span class="mw-page-title-main">Tricyclic antidepressant overdose</span> Medical condition

Tricyclic antidepressant overdose is poisoning caused by excessive medication of the tricyclic antidepressant (TCA) type. Symptoms may include elevated body temperature, blurred vision, dilated pupils, sleepiness, confusion, seizures, rapid heart rate, and cardiac arrest. If symptoms have not occurred within six hours of exposure they are unlikely to occur.

References

  1. Whittington RM (May 1963). "Mephentermine Sulphate as a Hypertensive Agent in General Practice". The Journal of the College of General Practitioners. 6 (2): 336–7. PMC   1878111 . PMID   14000433.
  2. William F Bruce, Szabo Joseph Lester, Tubis Samuel, U.S. Patent 2,597,445 (1952 to Wyeth Corp).
  3. Data, John B.; Skibbe, Martin O.; Kerley, T. Lamar; Weaver, Lawrence C. (1966). "Synthesis of N-Substituted Phenethylamines and Corresponding Cyclohexyl Analogs". Journal of Pharmaceutical Sciences. 55 (1): 38–43. doi:10.1002/jps.2600550108.
  4. Zenitz, Bernard L.; Macks, Elizabeth B.; Moore, Maurice L. (1948). "Preparation of α,α-Dimethyl- and N,α,α-Trimethyl-β-cyclohexylethylamine". Journal of the American Chemical Society. 70 (3): 955–957. doi:10.1021/ja01183a019.