Tylenol is considered to damage liver. Taking this many tablets may be toxic for the liver and this has to be ascertained by the liver function tests. There are no hard and fast rules for that as some individual do tolerate the same amount of medication for long while in some, liver may get compromised with these doses. So, an individual has to be investigated and monitored.
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The normal liver is under the right chest cage wall and cannot be felt. The pain is quite a rare sign of drug induced toxicity of the liver. The early signs are only by the liver enzyme estimations (blood work), as there are no symptoms. Since you have got the blood work done (liver function tests), and they are normal, you should not be worried.
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