Adverse reaction reports describe suspected side effects. A report does not mean the drug caused the event — co-medications, underlying disease and coincidence all contribute.
Who is the marketing authorisation holder for Hydroxide Potassium in United States?
Fundacio d'Investigacio en Atencio Primaria Jordi Gol i Gurina is the originator. The local marketing authorisation holder may differ — check the official source linked above.