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.
Normal concentrations of ammonia do not rule out hepatic encephalopathy. Other wastes can contribute to changes in mental function and consciousness, and brain levels of ammonia may be much higher than blood levels. This can make correlation of a person's symptoms to ammonia blood levels difficult. A decreased level of ammonia may be seen with some types of hypertension, such as essential (high blood pressure of unknown cause) and malignant (very high blood pressure that occurs suddenly and quickly). ^ Back to top.