Related Concept Videos

CNS Depressants: Alcohol and Nicotine01:27

CNS Depressants: Alcohol and Nicotine

Ethanol, a clear colorless alcohol, has been consumed by humans for millennia, but its effects on the body are far from benign. At lower doses, it induces decreased inhibitions and loquaciousness, leading to its social appeal. However, it can cause severe consequences at higher doses, such as coma and respiratory depression, due to its zero-order elimination kinetics. Chronic ethanol abuse wreaks havoc on multiple organ systems, particularly the CNS and the liver. Abrupt cessation of ethanol...
Sympathetic Activation01:16

Sympathetic Activation

The sympathetic division can influence tissues and organs by releasing norepinephrine at peripheral synapses and distributing epinephrine and norepinephrine through the bloodstream. In times of crisis or stress, sympathetic activation occurs, which is regulated by sympathetic centers in the hypothalamus. As a result, sympathetic activation prepares the body for physical exertion, rapid ATP production, and heightened alertness, allowing individuals to respond effectively to challenging or...
Adrenergic Agonists: Indirect-Acting Agents01:25

Adrenergic Agonists: Indirect-Acting Agents

Indirect-acting adrenergic agonists potentiate the effects of endogenous catecholamines through different mechanisms without directly binding to adrenoceptors.
One mechanism involves depleting stored catecholamines by displacing them from synaptic vesicles. These agents, known as "displacers," are transported into vesicles at the expense of noradrenaline. Examples include amphetamine and tyramine, which lack a catechol moiety, resulting in prolonged action, improved oral bioavailability, and...
Drugs Acting on Autonomic Ganglia: Stimulants01:23

Drugs Acting on Autonomic Ganglia: Stimulants


Ganglionic stimulants activate NM nicotinic receptors in autonomic ganglia, falling into two categories: nicotine mimetics [e.g., lobeline, dimethylpiperazine, tetramethylammonium] and muscarinic receptor agonists [e.g., muscarine, methacholine]. The first category's action is rapid and blocked by nicotinic receptor antagonists, while the second category's action is delayed and blocked by atropine-like agents. Nicotine, an alkaloid, affects the heart rate by stimulating sympathetic or...
CNS Stimulants: Cocaine, Amphetamines and Cannabinoids01:24

CNS Stimulants: Cocaine, Amphetamines and Cannabinoids

CNS stimulants, such as cocaine, amphetamines, and cannabinoids, have varying structures and mechanisms of action that lead to different therapeutic effects and side effects. Cocaine, with its molecular formula C17H21NO4, is a tropane alkaloid and a tertiary amino compound. It has two chemical forms: the hydrochloride salt and the "freebase." The former is in powder form, while the latter involves removing the hydrochloride salt to create a form that can be smoked. Cocaine exerts its effects by...
Toxidromes: Clinical Features01:30

Toxidromes: Clinical Features

Toxidromes are specific patterns of symptoms resulting from toxic substance exposure. They help in the identification and treatment of poisoning. The symptoms of each toxidrome group indicate poisoning by a certain class of chemicals or drugs.1. Sympathomimetic: Stimulates the sympathetic nervous system. Symptoms include agitation, increased heart rate (HR), blood pressure (BP), respiratory rate (RR), temperature, and pupil size. Drugs like cocaine and amphetamines, along with tremors and...