Search results
Results from the WOW.Com Content Network
Mydriasis is the dilation of the pupil, usually having a non-physiological cause, [3] or sometimes a physiological pupillary response. [4] Non-physiological causes of mydriasis include disease , trauma , or the use of certain types of drugs .
A 1998 study found a half-life of 4.1 ± 0.3 hours in young men, 7.4 ± 3.0 hours in elderly men, 4.4 ± 0.3 hours in young women, and 4.9 ± 0.6 hours in elderly women. [82] In a 2018 study in children and adolescents, the half-life of diphenhydramine was 8 to 9 hours. [83]
Clinical exam may reveal sectoral paresis of the iris sphincter or vermiform iris movements. The tonic pupil may become smaller (miotic) over time which is referred to as "little old Adie's". [5] Testing with low dose (1/8%) pilocarpine may constrict the tonic pupil due to cholinergic denervation supersensitivity. [1]
During this time, patients may be more light sensitive than normal and may notice close objects blurred (and possibly distant objects blurred, depending on the patient's visual system). Cyclopentolate is often chosen as a milder, shorter-lasting, cycloplegic alternative to atropine , another cycloplegic agent which lasts much longer.
Timeline: How the LA fires erupted into California’s worst natural disaster. New photos show the dangers residents face at their burned homes
Dilation and constriction of the pupil. Pupillary response is a physiological response that varies the size of the pupil, via the optic and oculomotor cranial nerve.. A constriction response (), [1] is the narrowing of the pupil, which may be caused by scleral buckles or drugs such as opiates/opioids or anti-hypertension medications.
Rarely, pseudoephedrine therapy may be associated with mydriasis (dilated pupils), hallucinations, arrhythmias, hypertension, seizures, and ischemic colitis; as well as severe skin reactions known as recurrent pseudo-scarlatina, systemic contact dermatitis, and non-pigmenting fixed drug eruption.
To say that mydriasis is "mainly caused by stimulation of the sympathetic system" is not entirely correct. SNS directly causes mydriasis and PNS interruption indirectly causes mydriasis - neither action is the main one. I'm not a neurologist but I believe mydriasis, whether pharmacologically induced or due to injury or other pathology, due to ...