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Hallucinogens, CNS Stimulants, And Cannabis
Published in S.J. Mulé, Henry Brill, Chemical and Biological Aspects of Drug Dependence, 2019
A host of α- and N-alkyl substituted derivatives have been prepared by the pharmaceutical chemist, evaluated by the experimental pharmacologist, and promptly exploited and abused by the socially active drug subculture. The N-methyl homolog of amphetamine (Benzedrine and Dexadrine, Figure 12, R1 = R2 = R3 = H) is methamphetamine (Figure 12, R1 = R2 = H, R3 = CH3). This chemical has no medical virtue over amphetamine itself, but has been abused greatly for its stimulant action. In an effort to circumvent abuse, the homolog mephentermine has been substituted as a decongestant inhalent, but this chemical (Wyamine®, Figure 12, R1 = H, R2 = R3 = CH3) promptly found an abuse market as an excitant.36 The beta-hydroxy analogs of these chemicals, members of the Ephedra botanical group, have been long known as stimulants. A number of these have come into the pharmacological literature (ephedrine and phenylpropanolamine, Figure 12, R1 = OH, R2 = H, R3 = H or CH3) and encountered the illicit drug trade.
Percutaneous transvenous mitral commissurotomy: Techniques and hardware
Published in Neeraj Parakh, Ravi S. Math, Vivek Chaturvedi, Mitral Stenosis, 2018
Sudden bradycardia, significant hypotension, and even asystole may sometimes occur during or just after balloon dilatation and may not recover immediately. Intravenous atropine, IV mephentermine, and temporary pacing leads should be ready and used immediately for recovery.
Drugs Affecting Storage and Release from Sympathetic Neurones
Published in Kenneth J. Broadley, Autonomic Pharmacology, 2017
Other characteristic features of adrenergic neurone blockade are the effects of frequency of nerve stimulation and interactions with other drugs acting on the neurone. The blockade of responses to sympathetic nerve stimulation by guanethidine is frequency-dependent, with preferential inhibition of lower frequencies of stimulation. The frequency-response curves are therefore shifted to the right in an approximately parallel manner. Bretylium, however, depresses the maximum of the frequency-response curve. Interactions with other drugs include the reversal of blockade by indirectly acting sympathomimetic amines, such as dexamphetamine (Figure 6.7), phenylethylamine and mephentermine, although tyramine may be active only in vitro. The blockade is not consistently reversed or prevented by directly acting sympathomimetic amines, such as the catecholamines noradrenaline and adrenaline, nor by MAO inhibitors, providing they do not have indirect activity. These features contrast with blockade by reserpine (see later). The blockade is reversed by neuronal uptake inhibitors, such as cocaine and imipramine (Boura & Green 1965). In view of these interactions, the concomitant use of sympathomimetics, for example as nasal decongestants, and of the tricyclic antidepressants is contraindicated.
Mephentermine Misuse: An Impending Crisis among Sportspersons
Published in Journal of Psychoactive Drugs, 2022
Akansha Bhardwaj, Jagriti Yadav, Sidharth Arya, Rajiv Gupta
Mephentermine is a sympathomimetic amine with a mixed mechanism of action. It acts primarily as a selective alpha-1 receptor agonist and indirectly by releasing norepinephrine, resulting in increased cardiac contraction, increased systolic, and diastolic blood pressure, eventually leading to increased cardiac output (Westfall, Macarthur, and Westfall 2011). It is commonly administered as an intravenous bolus of 3–5 mg or as an intravenous infusion of 2–5 mg/min (Kansal et al. 2005). Although currently banned in certain countries, it is still used for management of hypotension during spinal anesthesia in humans (Fitzgerald et al. 2020; Westfall, Macarthur, and Westfall 2011) and for veterinary purposes (Cunha et al. 2018). Common side effects of mephentermine include dry mouth, sedation, reflex bradycardia, arrhythmias, and hypertension (Westfall, Macarthur, and Westfall 2011). Severe complications such as refractory hypertension, cardiomyopathy (Singal et al. 2020), acute agitation, psychosis, and delirium (Oliveira et al. 2011) have also been reported in the literature.
Herculean mistake: mephentermine associated cardiomyopathy
Published in The Physician and Sportsmedicine, 2021
Aayush Kumar Singal, Siddharthan Deepti, Gautam Sharma, Shyam S. Kothari
Mephentermine is an indirectly acting sympathomimetic agent that acts by causing epinephrine and norepinephrine release. Though we found no reports associating mephentermine use to cardiomyopathy, we hypothesize that mephentermine led to the acute LV dysfunction in our patient as there was a temporal correlation of its use, withdrawal, and resumed consumption with symptoms. Mephentermine resembles methamphetamine, both structurally and physiologically. It is recognized that methamphetamine abuse leads to LV dysfunction through drug-induced vasospasm and ischemia, direct toxicity, as well as deleterious effects of excess catecholamines on cardiomyocytes. Methamphetamine-associated-cardiomyopathy is a recognized entity [4]. In rat model, continuous nor-epinephrine infusion has been shown to result in cardiac fibrosis and dysfunction [5]. Increased epinephrine and norepinephrine levels in pheochromocytoma are associated with reversible cardiomyopathy [6]. Cocaine is also an indirectly acting sympathomimetic agent and leads to increased cardiovascular stress by causing coronary spasm, increasing myocardial oxygen demand, and creating a procoagulant state [7]. Thus, it is biologically plausible that by creating a catecholamine high state, mephentermine can also cause cardiomyopathy.
Mephentermine dependence with induced psychosis: a series of two cases
Published in Journal of Substance Use, 2020
Anuranjan Vishwakarma, Jatin Tarwani, Nishtha Chawla, Prabhoo Dayal, Alok Agrawal, Piyali Mandal, Atul Ambekar
Mephentermine is an α-adrenergic agonist, indicated for treatment of hypotensive states commonly seen in spinal anaesthesia, shock and myocardial infarction. It mainly acts on monoaminergic synapses in brain which release noradrenaline, dopamine and serotonin (King & Ellinwood, 1997; Wisher, 2012). It is converted into amphetamine by demethylation, stimulating the central nervous system indirectly (Docherty, 2008). Mephentermine is sometimes misused for enhancing physical performance by athletes, but the data available on its dependence potential as well as potential to induce psychosis is limited (Oliveira et al., 2011). We present two cases of mephentermine use in dependent pattern with induced psychosis.