A 72-year-old man with COPD and ischaemic heart disease reports a sore mouth during hospitalisation. Which inhaled medication is the most likely cause of the sore mouth?

• A. Beclometasone inhaler alone
• B. DuoResp Spiromax 160/4.5
• C. Salmeterol inhaler
• D. Tiotropium inhaler

Answer: (B)

Inhaled corticosteroids can cause local immune suppression in the mouth and throat, which allows Candida to overgrow and leads to oral thrush or a sore mouth. The risk rises with higher doses of corticosteroid and with formulations that deliver more steroid to the oropharyngeal area. Among the options, the inhaler that provides budesonide 160 mcg per actuation as part of a budesonide/formoterol combination delivers a relatively high inhaled corticosteroid dose, making it the most likely culprit for a sore mouth. Beclometasone alone is a corticosteroid too but generally used at a lower dose per actuation; salmeterol is a long-acting beta-agonist without corticosteroid, and tiotropium is an anticholinergic bronchodilator without steroids. Therefore, the budesonide-containing inhaler is the most likely cause. Rinsing the mouth after inhalation and using a spacer can help reduce this side effect.