Common symptoms of high ammonia:
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Feeling very tired
or sluggish
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Staring or
"zoning out"
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Nausea
or vomiting
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Losing touch with
reality/hallucinating
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Unusually irritable
or uncooperative
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Aggression
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Lack of appetite
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Slurring words
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Headache
Symptoms of a urea cycle disorder (UCD) may appear at any time and can vary from person to person. Normal things in life, like being sick, stressed out, and eating foods that are high in protein, can cause ammonia to rise to toxic levels. This can trigger a hyperammonemic crisis. A hyperammonemic crisis is when there is an extremely high level of ammonia in the blood and it requires immediate medical attention. Even mild symptoms can mean that the ammonia level in the body has risen to a high level that can lead to serious health problems if not treated.
Symptoms like these should not be ignored, because they may be signs of high levels of ammonia, which can lead to comas or permanent brain damage.