After taking ceain medications an adolescent ended up in metabolic acidosis. The causative drug will be:

The carbonic anhydrase inhibitor acetazolamide induces metabolic acidosis and thereby stimulates ventilation, but it is not widely used because the metabolic imbalance it produces may be detrimental in the face of respiratory acidosis. It has a very small beneficial effect in respiratory failure in COPD patients. The drug has proved useful in prevention of high altitude sickness. Ref: Barnes P.J. (2011). Chapter 36. Pulmonary Pharmacology. In L.L. Brunton, B.A. Chabner, B.C. Knollmann (Eds), Goodman & Gilman's The Pharmacological Basis of Therapeutics, 12e.