Atropine degrades slowly, typically wearing off in 7 to 14 days, so it is generally used as a therapeutic mydriatic, whereas tropicamide (a shorter-acting cholinergic antagonist) or phenylephrine (an Î±-adrenergic agonist) is preferred as an aid to ophthalmic examination.
Read More. The normal ammonia range is 10â47 Î¼mol/L. High ammonia levels and signs of hepatic encephalopathy is a worsening of brain function that occurs when the liver is no longer able to remove toxic substances in the blood due to cirrhosis. Symptoms may be mild at first.
Clinical Significance. Ammonia is one of the by-products of protein metabolism. Elevated blood ammonia levels have been associated with severe liver dysfunction such as hepatic encephalopathy, coma resulting from cirrhosis, severe hepatitis, Reye's syndrome, and drug hepatotoxicity. Also, elevated blood ammonia has been reported in cardiac failure, azotemia, and pulmonary emphysema. Correlation between plasma ammonia and the degree of encephalopathy can be erratic.