Tag: Autonomic nervous system

In 2020, an estimated 5.1 million people aged 12 or older in the United States misused prescription stimulants [1.8.1]. A key physiological sign associated with stimulant use is a change in pupil size, but do stimulants dilate or constrict your pupils?

Opioids, including heroin, fentanyl, and prescription painkillers, were involved in nearly 70,000 overdose deaths in the U.S. in 2021 alone. A tell-tale sign of opioid use, particularly in overdose situations, is a change in pupil size. But do opioids make pupils dilate or constrict? The answer lies in their specific effect on the nervous system, which causes pupil constriction, or miosis.

The parasympathetic nervous system (PNS) is responsible for the body's 'rest and digest' functions, and parasympathomimetics are a class of medications that activate this system by mimicking the effects of the primary neurotransmitter, acetylcholine. Understanding what are the effects of parasympathomimetics is crucial for healthcare professionals and patients alike, as these drugs are used to treat a variety of conditions, from glaucoma to urinary retention.

Historically, concerns have been raised regarding the use of atropine in individuals with Down syndrome (Trisomy 21), driven by reports of increased susceptibility to toxic effects. This has led to a traditional caution and, in many cases, a firm belief that atropine is contraindicated in Down syndrome patients due to their unique physiological profile, particularly concerning the autonomic nervous system.

Phencyclidine (PCP) intoxication commonly presents with both nystagmus and dilated pupils, with a specific type of nystagmus (rotary) being a key diagnostic feature. Identifying what drug causes nystagmus and dilated pupils is crucial for healthcare providers in emergency settings to diagnose and manage potential drug toxicity or overdose.

The heart has five fundamental properties that govern its function, first described in 1897. This guide breaks down what is inotropic vs chronotropic vs dromotropic vs bathmotropic by exploring how medications and the nervous system precisely modulate the heart's rate, contractility, electrical conduction, and excitability.

The human heart beats approximately 100,000 times per day, and understanding how different medications influence its function is fundamental in pharmacology. Master the core concepts of cardiac medication by learning how to remember chronotropic, inotropic, and dromotropic effects through easy-to-use mnemonics and clear explanations.

The size of the human pupil is regulated by a delicate balance between the sympathetic and parasympathetic nervous systems. Numerous substances can influence this system, leading to a visible constriction (miosis) or dilation (mydriasis) of the pupils. This guide explains exactly what drugs constrict vs dilate pupils, exploring the specific pharmacological mechanisms behind these changes.

Atropine is a critical medication in emergency and cardiac care, with its mechanism of action often confused with other drug classes. Understanding its true pharmacological identity is vital, especially when considering the question: **is atropine an alpha or beta blocker?** The answer, rooted in the autonomic nervous system, clarifies atropine's distinct role.

According to research, dilated pupils, or mydriasis, can be a visible indicator of drug use, with substances interfering with the normal functioning of the nervous system. Understanding which substance causes dilated pupils requires exploring how different compounds interact with the body's involuntary nervous system and iris muscles.