Salicylates are a group of chemicals derived from salicylic acid. E.g. aspirin (acetylsalicylic acid), salicylic acid, bismuth subsalicylate (Pepto-Bismol), Mesalamine (5-aminosalicylic acid), etc.
Salicylate overdose causes a high anion gap metabolic acidosis in both children and adults and respiratory alkalosis 2/2 to hyperventilation in adults.
Direct stimulation of the respiratory center in the brain causes hyperventilation and respiratory alkalosis.
Mitochondrial dysfunction → high lactate levels → metabolic acidosis.
“As it is metabolized, it causes an uncoupling of oxidative phosphorylation in the mitochondria. Lactate levels then increase due to the increase in anaerobic metabolism. The lactic acid along with a slight contribution from the salicylate metabolites result in metabolic acidosis. Hyperventilation worsens in an attempt to compensate for the metabolic acidosis. Eventually, the patient fatigues and is no longer able to compensate via hyperventilation, and metabolic acidosis prevails. This results in hemodynamic instability and end-organ damage.”A
Source:
https://www.anaesthesiamcq.com/AcidBaseBook/ab8_6c.php