This is an open-label, randomized, single-center, 2-period, 2-sequence, single-dose crossover design study in adult male and female healthy participants. Eligible participants will receive either treatment A (reference): Fluimucil® Acetylcysteine 2% oral solution, 200 mg N- acetylcysteine (NAC) in 10 mL dose, or treatment B (test): Acetylcysteine 2% oral solution, 200 mg NAC in 10 mL dose. Blood sampling will be collected pre-dose and up to 48 hours in each period. After completion of the second study period (i.e. last pharmacokinetic (PK) sample on Day 3 of Period 2) participants will be discharged from the clinic.