Fixed dilated pupil6/19/2023 Several household or garden plants found in North America contain high concentrations of alkaloids including atropine, scopolamine, hyoscine, and hyoscyamine. Topical exposure to environmental toxins such as Jimson weed (Datura stramonium) or bella donna alkaloids can also produce mydriasis. In contrast, the unilateral dilated pupil is usually due to local or topical exposure to an assortment of dilating agents (e.g., mydriatic drops).Īnticholinergic mydriasis, also known as pharmacologic blockade and “atropinic” mydriasis, refers to the absolute or partial paralysis of pupillary constriction unilaterally or bilaterally due to topical advertent or inadvertent exposure to an anticholinergic agent. This effect is usually accompanied by other signs of central nervous system involvement, such as depression, agitation, and altered level of consciousness. Most commonly, the medications, drugs, and toxins that cause pupillary dilation act via iris parasympathetic receptor blockade (anticholinergic mydriasis) but sympathetic stimulation (e.g., topical epinephrine) can also produce lesser degrees of pharmacologic mydriasis (without impairing the light/near reaction).Īgents that affect the central nervous system such as atropine, scopolamine, amphetamine, marijuana, lysergic acid diethylaminde (LSD), and glutethimide can cause bilateral mydriasis. Clinical differentiation from similar appearing life-threatening pathologies, most notably compressive lesions of cranial nerve III, is vital. It is typically characterized by poor or no pupillary constriction to light or near stimuli. ![]() Pharmacologic dilation of the pupil is one of the myriad explanations for unilateral or bilateral pupillary dilation.
0 Comments
Leave a Reply. |