The key difference between N acetyl L cysteine and N acetylcysteine is that the term N acetyl L cysteine states that this compound is the N-acetyl derivative of the amino acid L-cysteine whereas N acetylcysteine is the same compound as N acetyl L cysteine but the name does not give details about L cysteine.
Acetylcysteine is a medication that we use to treat paracetamol overdose. Moreover, we can use it to loosen thick mucus in individuals with cystic fibrosis. N-acetyl-cysteine, N-acetylcysteine, N-acetyl cysteine, and N-acetyl-L-cysteine are all designations for the same compound. Just the details given by the two terms N acetyl L cysteine and N acetylcysteine are different from each other.
