Category: Fundamentals Methylenedioxymethamphetamine (MDMA, ecstasy, XTC, Adam) is a chemically modified amphetamine taken orally at all-night dance parties. Patients describe the euphoria allowing “closeness to others,” so it is sometimes called the love drug.
Category: Fundamentals Amphetamines put patients at risk for hypertensive emergencies, dysrhythmias, myocardial ischemia and hyperkalemia associated with rhabdomyolysis. In contrast to cocaine, amphetamines do not block sodium channels.
Category: Fundamentals Amphetamines enhance the release of catecholamines from presynaptic nerve terminals by altering the pH of presynaptic vesicles. Amphetamines are usually taken as pills but are occasionally crushed and injected.
Category: Fundamentals Cocaine induces coronary vasoconstriction while increasing myocardial oxygen demand. Platelet aggregation is enhanced through thrombogenic and antifibrinolytic pathways. These cumulative effects can result in coronary insufficiency.
Category: Fundamentals Dysrhythmias from cocaine may be atrial or ventricular. Atrial fibrillation and supraventricular tachycardias are likely to be due to sympathetic stimulation and often respond to benzodiazepines.
Category: Fundamentals Although sinus tachycardia is the most common rhythm in cocaine toxicity, atrial fibrillation and other supraventricular tachycardias can occur as a result of the surge in catecholamines. Life-threatening dysrhythmia may occur suddenly.
Category: Fundamentals Acute cocaine-induced hypertension can cause serious injury to the cardiovascular and central nervous systems. Reported sequelae include aortic dissection, pulmonary edema, myocardial infarction, intracranial hemorrhage and stroke.
Category: Fundamentals Cocaine toxic patients have increased motor tone and generate excessive heat. Vasoconstriction and salt and water depletion can compromise cooling, resulting in life-threatening hyperthermia with core temperatures exceeding 106° F (41.1° C).
Category: Fundamentals The primary clinical effect of cocaine is the excitation of the sympathetic nervous system. Patients with moderate toxicity are alert and awake but may have diaphoresis, tachycardia, mydriasis and hypertension without organ damage.
Category: Fundamentals Norepinephrine causes vasoconstriction by stimulation of alpha-adrenergic receptors on vascular smooth muscle. Epinephrine increases myocardial contractility and heart rate through stimulation of beta1-adrenergic receptors.
Category: Fundamentals Cocaine use causes the release of dopamine, epinephrine, norepinephrine and serotonin. These neurotransmitters act on different receptor subtypes with the most important being adrenergic stimulation by norepinephrine and epinephrine.
Category: Fundamentals Cocaine, amphetamines and derivatives of amphetamines are called sympathomimetics. These agents cause central nervous system (CNS) stimulation and a cascade of adrenergic physiologic effects.
Category: Fundamentals The use of nitrates is contraindicated in patients who have recently taken sildenafil (Viagra). Sildenafil and related drugs relax vascular smooth muscle, which prolong and intensify the vasodilating effects of nitrates, resulting in severe hypotension.
Category: Fundamentals Nitroglycerin infusions are used commonly in patients with acute pulmonary edema for afterload reduction. IV nitroglycerin has a rapid offset of action and an excessive fall in blood pressure may occur.
Category: Fundamentals Some nitrate exposures occur in young adults, usually male, who inhale alkyl nitrites in the hope of enhancing sexual pleasure. Because of the sound they make when broken open, these products are best known to abusers as “poppers.”
