On February 15, 2022, the German Federal Institute for Drugs and Medical Devices (BfArM) published an implementation notice for the approval of the active ingredient combination hydrochlorothiazide/spironolactone, calling for a change in the product information and directions for use. But what is the basis for this demand and what changes will be included?
Two European procedures evaluating the periodic safety reports were carried out for drugs with the active substance combination hydrochlorothiazide/spironolactone and new findings were assessed. Taking these into account, the Pharmacovigilance Risk Assessment Committee (PRAC) of the European Medicines Agency (EMA) took the decision to adapt the product information and directions for use for the drug combination hydrochlorothiazide/spironolactone to the new state of knowledge. In future, reference will be made to the risk of acute respiratory toxicity in both product information leaflets.
Background for the changes
The need to refer to this risk is fed by several sources. These include literature data on acute respiratory syndrome and spontaneous reports of some cases of a close temporal association between the use of hydrochlorothiazide/spironolactone and the occurrence of acute respiratory distress syndrome. Based on a positive re-challenge and a plausible mechanism of action, the PRAC believes that a causal relationship exists between hydrochlorothiazide/spironolactone and acute respiratory distress syndrome and that a warning is needed to inform healthcare professionals about acute respiratory toxicity.
Adaptation of the package leaflet
The following two statements should be included in the package insert:
„Please talk to your doctor or pharmacist or healthcare professional before using [this medicine] … if you have a history of breathing or lung problems (including inflammation or fluid build-up in the lungs) after taking hydrochlorothiazide. If you develop severe shortness of breath or difficulty breathing after taking [this medicine], see a doctor right away.“ and
„What are the possible side effects? Very rare: Acute shortness of breath (signs include severe shortness of breath, fever, weakness, and confusion).“