L-cysteine is an important protein and a deficiency could cause serious health problems. L-cysteine is commonly used to help prevent major organ damage that can be caused by taking acetaminophen. In certain dietary supplement form, L-cysteine counteracts the mild pain reliever and its effects on the liver.
L-Cysteine
L-cysteine, or N-acetyl-L-cysteine, or NAC, is the supplement form of cysteine, an amino acid. Amino acids are building blocks of protein and are found throughout the body. Your body converts the dietary supplement into cysteine, and then into glutathione, an effective antioxidant that fights free radicals in your body, according to the University of Maryland Medical Center, or UMMC.
Acetaminophen
Acetaminophen, better known by the brand name Tylenol, is widely used to help relieve mild and moderate pains caused by a variety of common conditions, such as headaches and toothaches. It is also commonly used to help reduce fevers. Tylenol can be taken safely when following dosage directions without the risk of any serious side effects. An acetaminophen overdose can result in pain in the upper right part of the stomach, according to MedlinePlus, a sign that the liver is being damaged by the pain reliever.
Acetaminophen Poisoning
Acetaminophen poisoning can occur when too much of the pain reliever is taken. The excess acetaminophen can cause liver damage, as well as damage to other vital organs. The pain reliever depletes the liver of its glutathione stores, according to Merck.com, and instead stores a toxic metabolite of acetaminophen, causing damage to the organ. To treat the poisoning, L-cysteine is given intravenously to prevent or reduce liver damage and help restore the glutathione level.
Alcoholism and Malnutrition
Acetaminophen poisoning can also take place if the recommended dosage is taken but mixed with alcohol or certain medications, according to the UMMC. Alcoholics and people with malnutrition are at a greater risk of liver damage, according to Merck. The toxic metabolite delivered through acetaminophen is more easily stored in the liver due to the organ's weak condition and low glutathione level.
L-Cysteine Side Effects
As with any dietary supplement, you should consult your doctor before taking any L-cysteine supplement. High doses of the supplement may be toxic to humans or even result in death, notes the UMMC. NAC given intravenously for acetaminophen poisoning can cause allergic reactions, including anaphylaxis, a life-threatening allergy, according to the UMMC.
