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Convulsant
A convulsant is a drug which induces convulsions or epileptic seizures, the opposite of an anticonvulsant. These drugs generally act as stimulants at low doses, but are not used for this purpose due to poor therapeutic indices. Most convulsants are antagonists (or inverse agonists) at either the GABAA or/and glycine receptors (e.g the pesticide fipronil), or ionotropic glutamate receptor agonists (e.g the marine toxin domoic acid). Many other drugs may cause convulsions as a side effect at high doses (e.g. bupropion, tramadol, pethidine, dextropropoxyphene, clomipramine) but only drugs whose primary action is to cause convulsions are known as convulsants. Nerve agents such as sarin, which were developed as chemical weapons, produce convulsions as a major part of their toxidrome, but also produce a number of other effects in the body and are usually classified separately. Dieldrin which was developed as an insecticide blocks chloride influx into the neurons causin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentetrazol
Pentylenetetrazol (PTZ), also known as pentylenetetrazole, pentetrazol ( INN), and pentamethylenetetrazol, is a drug formerly used as a circulatory and respiratory stimulant. High doses cause convulsions, as discovered by Hungarian-American neurologist and psychiatrist Ladislas J. Meduna in 1934. It has been used in convulsive therapy, and was found to be effective in treating depression, but side effects such as uncontrolled seizures were difficult to avoid. In 1939, pentylenetetrazol was replaced by electroconvulsive therapy, which is easier to administer, as the preferred method for inducing seizures in England's mental hospitals. In the US, Pentylenetetrazol's approval by the Food and Drug Administration (FDA) was revoked in 1982. It is used in Italy as a cardio-respiratory stimulant in combination with dihydrocodeine in a cough suppressant drug. Side effects Pentylenetetrazol is anxiogenic and has been known to induce severe anxiety in humans. Mechanism of action The m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fipronil
Fipronil is a broad-spectrum insecticide that belongs to the phenylpyrazole insecticide class. Fipronil disrupts the insect central nervous system by blocking the ligand-gated ion channel of the GABAA receptor ( IRAC group 2B) and glutamate-gated chloride (GluCl) channels. This causes hyperexcitation of contaminated insects' nerves and muscles. Fipronil's specificity towards insects is believed to be due to its greater binding affinity for the GABAA receptors of insects than to those of mammals, and for its action on GluCl channels, which do not exist in mammals. , there does not appear to be significant resistance among fleas to fipronil. Fipronil is used as the active ingredient in flea control products for pets and home roach baits as well as field pest control for corn, golf courses, and commercial turf. Its widespread use makes its specific effects the subject of considerable attention. Observations on possible harm to humans or ecosystems are ongoing as well as the mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Domoic Acid
Domoic acid (DA) is a kainic acid-type neurotoxin that causes amnesic shellfish poisoning (ASP). It is produced by algae and accumulates in shellfish, sardines, and anchovies. When sea lions, otters, cetaceans, humans, and other predators eat contaminated animals, poisoning may result. Exposure to this compound affects the brain, causing seizures, delirium and possibly death. History There has been little use of domoic acid throughout history except for in Japan, where it has been used as an anthelmintic for centuries. Domoic acid was first isolated in 1959 from a species of red algae, ''Chondria (alga), Chondria armata'', in Japan, which is commonly referred to as ''dōmoi'' (ドウモイ) in the Tokunoshima dialect, or ''hanayanagi''. Poisonings in history have been rare, or undocumented; however, it is thought that the increase in human activities is resulting in an increasing frequency of harmful algal blooms along coastlines in recent years. In 2015, the North American Pacific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pethidine
Pethidine, also known as meperidine and sold under the brand name Demerol among others, is a fully synthetic opioid pain medication of the phenylpiperidine class. Synthesized in 1938 as a potential anticholinergic agent by the German chemist Otto Eisleb, its analgesic properties were first recognized by Otto Schaumann while working for IG Farben, in Germany. Pethidine is the prototype of a large family of analgesics including the pethidine 4-phenylpiperidines (e.g., piminodine, anileridine), the prodines (e.g., alphaprodine, MPPP), bemidones (e.g., ketobemidone), and others more distant, including diphenoxylate and analogues. Pethidine is indicated for the treatment of moderate to severe pain, and is delivered as a hydrochloride salt in tablets, as a syrup, or by intramuscular, subcutaneous, or intravenous injection. For much of the 20th century, pethidine was the opioid of choice for many physicians; in 1975, 60% of doctors prescribed it for acute pain and 22% for chroni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Therapeutic Index
The therapeutic index (TI; also referred to as therapeutic ratio) is a quantitative measurement of the relative safety of a drug with regard to risk of overdose. It is a comparison of the amount of a therapeutic agent that causes toxicity to the amount that causes the therapeutic effect. The related terms therapeutic window or safety window refer to a range of doses optimized between efficacy and toxicity, achieving the greatest therapeutic benefit without resulting in unacceptable side-effects or toxicity. Classically, for clinical indications of an approved drug, TI refers to the ratio of the dose of the drug that causes adverse effects at an incidence/severity not compatible with the targeted indication (e.g. toxic dose in 50% of subjects, TD) to the dose that leads to the desired pharmacological effect (e.g. efficacious dose in 50% of subjects, ED). In contrast, in a drug development setting TI is calculated based on plasma exposure levels. In the early days of pharmaceu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nerve Agent
Nerve agents, sometimes also called nerve gases, are a class of organic chemistry, organic chemicals that disrupt the mechanisms by which nerves transfer messages to organs. The disruption is caused by the blocking of acetylcholinesterase (AChE), an enzyme that catalyzes the breakdown of acetylcholine, a neurotransmitter. Nerve agents are irreversible acetylcholinesterase inhibitors used as poison. Poisoning by a nerve agent leads to constriction of pupils, profuse salivation, convulsions, and involuntary urination and defecation, with the first symptoms appearing in seconds after exposure. Death by asphyxiation or cardiac arrest may follow in minutes due to the loss of the body's control over Respiration (physiology), respiratory and other muscles. Some nerve agents are readily vaporized or aerosolized, and the primary portal of entry into the body is the respiratory system. Nervous agents can also be absorbed through the skin, requiring that those likely to be subjected to su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Febrile Seizure
A febrile seizure, also known as a fever fit or febrile convulsion, is a seizure associated with a high body temperature but without any serious underlying health issue. They most commonly occur in children between the ages of 6 months and 5 years. Most seizures are less than five minutes in duration, and the child is completely back to normal within an hour of the event. There are two types: simple febrile seizures and complex febrile seizures. Simple febrile seizures involve an otherwise healthy child who has at most one tonic-clonic seizure lasting less than 15 minutes in a 24-hour period. Complex febrile seizures have focal symptoms, last longer than 15 minutes, or occur more than once within 24 hours. About 80% are classified as simple febrile seizures. Febrile seizures are triggered by fever, typically due to a viral infection. They may run in families. The underlying mechanism is not fully known, but it is thought to involve genetics, environmental factors, brain immatu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antihistamine
Antihistamines are drugs which treat allergic rhinitis, common cold, influenza, and other allergies. Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provides relief from nasal congestion, sneezing, or hives caused by pollen, dust mites, or animal allergy with few side effects. Antihistamines are usually for short-term treatment. Chronic allergies increase the risk of health problems which antihistamines might not treat, including asthma, sinusitis, and lower respiratory tract infection. Consultation of a medical professional is recommended for those who intend to take antihistamines for longer-term use. Although the general public typically uses the word "antihistamine" to describe drugs for treating allergies, physicians and scientists use the term to describe a class of drug that opposes the activity of histamine receptors in the body. In this sense of the word, antihistamines are subc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theophylline/ephedra/hydroxyzine
Theophylline/ephedra/hydroxyzine (trade name Marax) is a drug that was used for the treatment of asthma. It was a combination of theophylline, ephedra, and hydroxyzine, and taken by mouth. It is no longer manufactured in the US due to approval of ephedra being withdrawn by the FDA The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food .... See also * Theophylline/ephedrine References Bronchodilators Combination drugs {{respiratory-system-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piperazine
Piperazine () is an organic compound with the formula . In term of its structure, it can be described as cyclohexane with the 1- and 4-CH2 groups replaced by NH. Piperazine exists as deliquescent solid with a saline taste. Piperazine is freely soluble in water and ethylene glycol, but poorly soluble in diethyl ether. Piperazine is commonly available industrially is as the hexahydrate, , which melts at 44 °C and boils at 125–130 °C.''The Merck index, 10th Ed.'' (1983), p. 1076, Rahway:Merck & Co. Substituted derivatives of piperazine are a broad class of chemical compounds. Many piperazines have useful pharmacological properties, prominent examples include viagra, ciprofloxacin, and ziprasidone. Origin and naming Piperazines were originally named because of their chemical similarity with piperidine, part of the structure of piperine in the black pepper plant (''Piper nigrum''). The -az- infix added to "piperazine" refers to the extra nitrogen atom, compared to piperidine. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terpene
Terpenes () are a class of natural products consisting of compounds with the formula (C5H8)n for n ≥ 2. Terpenes are major biosynthetic building blocks. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly Pinophyta, conifers. In plants, terpenes and terpenoids are important mediators of ecological biological interaction, interactions, while some insects use some terpenes as a form of defense. Other functions of terpenoids include cell growth modulation and plant elongation, light harvesting and photoprotection, and membrane permeability and fluidity control. Terpenes are classified by the number of carbons: monoterpenes (C10), sesquiterpenes (C15), diterpenes (C20), as examples. The terpene alpha-pinene is a major component of the common solvent, turpentine. The one terpene that has major applications is natural rubber (i.e., polyisoprene). The possibility that other terpenes could be used as precursors to pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
