Toxicology

Anticholinergic Toxidrome

TRAntikolinerjik Toksidrom
Also known as:Antimuscarinic toxidrome · Anticholinergic syndrome

A clinical syndrome caused by blockade of muscarinic acetylcholine receptors, characterised by delirium, tachycardia, hyperthermia, mydriasis, dry flushed skin, urinary retention and reduced bowel sounds.

In depth

Competitive antagonism at central muscarinic receptors causes agitation, disorientation, mumbling speech, visual hallucinations and picking movements, progressing to seizures and coma in severe cases. Peripheral blockade produces sinus tachycardia, dry mucous membranes, absent sweating, flushing, mydriasis with blurred vision, ileus and urinary retention; hyperthermia reflects impaired sweating and agitation.

Common causes are first-generation antihistamines, tricyclic antidepressants, antipsychotics, antiparkinsonian and antispasmodic antimuscarinics, and plants such as Datura and Atropa species. Management is supportive: benzodiazepines for agitation, external cooling, bladder catheterisation and continuous ECG monitoring, with sodium bicarbonate if QRS widening indicates sodium-channel blockade (e.g. tricyclics, diphenhydramine).

Clinical pearl

Physostigmine, a tertiary-amine cholinesterase inhibitor that crosses the blood–brain barrier, can reverse anticholinergic delirium but should be given only with cardiac monitoring and avoided when the ECG shows QRS widening or tricyclic poisoning is suspected.

Example drugs

Atropine Diphenhydramine Amitriptyline Benzatropine Oxybutynin
TRIn Turkish

Antikolinerjik Toksidrom

Muskarinik asetilkolin reseptörlerinin blokajı sonucu gelişen; deliryum, taşikardi, hipertermi, midriyazis, kuru ve kızarık cilt, idrar retansiyonu ve azalmış bağırsak sesleriyle karakterize klinik sendromdur.

Merkezi muskarinik reseptörlerdeki yarışmalı antagonizma ajitasyon, oryantasyon bozukluğu, mırıldanarak konuşma, görsel halüsinasyonlar ve toplama hareketlerine (karfoloji) yol açar; ağır olgularda nöbet ve koma gelişebilir. Periferik blokaj sinüs taşikardisi, mukozalarda kuruluk, anhidroz, ciltte kızarma, bulanık görmeyle birlikte midriyazis, ileus ve idrar retansiyonu oluşturur; hipertermi terlemenin bozulması ve ajitasyonla ilişkilidir.

Sık nedenler birinci kuşak antihistaminikler, trisiklik antidepresanlar, antipsikotikler, antiparkinson ve antispazmodik antimuskarinik ilaçlar ile tatula (Datura) ve güzelavratotu (Atropa) gibi bitkilerdir. Tedavi destekleyicidir: ajitasyon için benzodiazepinler, dış soğutma, mesane kateterizasyonu ve sürekli EKG izlemi uygulanır; QRS genişlemesi sodyum kanalı blokajını gösteriyorsa (ör. trisiklikler, difenhidramin) sodyum bikarbonat verilir.

Kan–beyin bariyerini geçen tersiyer amin yapılı kolinesteraz inhibitörü fizostigmin antikolinerjik deliryumu geri döndürebilir; ancak yalnızca kardiyak monitörizasyonla verilmeli, EKG'de QRS genişlemesi varsa veya trisiklik zehirlenmesinden şüpheleniliyorsa kullanılmamalıdır.

Diğer adları:Antimuskarinik toksidrom · Antikolinerjik sendrom
Updated 24.09.2026 0 views Educational reference — verify against current sources before clinical use.

Read next

ToxidromeToksidrom

A constellation of signs and symptoms (vital signs, mental status, pupils, skin and bowel sounds) characteristic of poisoning by a particular class of agents, used to identify the likely cause at the bedside.

 Cholinergic ToxidromeKolinerjik Toksidrom

A clinical syndrome of excess acetylcholine activity at muscarinic and nicotinic receptors, most often from acetylcholinesterase inhibition, producing copious secretions, bronchospasm, bradycardia, miosis, fasciculations and weakness.

 AntidoteAntidot

A substance that counteracts the effects of a poison or drug overdose by preventing its absorption, binding or inactivating it, antagonising it at its site of action, enhancing its elimination or reversing its toxic effects.

 Competitive AntagonismYarışmalı Antagonizma

Reversible antagonism in which the antagonist binds to the same site as the agonist, so the block can be overcome by raising the agonist concentration; the agonist curve shifts to the right in parallel without a fall in maximal response.

 Blood–Brain BarrierKan–Beyin Bariyeri

A selective barrier formed by brain capillary endothelial cells joined by tight junctions and supported by pericytes and astrocyte end-feet, which restricts the passage of drugs and solutes from blood into the central nervous system.

 Potentially Inappropriate MedicationPotansiyel Olarak Uygunsuz İlaç

A medicine whose risks outweigh its expected benefits in a particular patient or population, typically older adults, especially when a safer or more effective alternative exists.