❌ I am taking a medicine for my stomach.
✅ I'm taking medicine for my stomach / I'm on stomach medication.
의약품을 나타낼 때는 보통 'medicine'이나 'medication'을 셀 수 없는 명사로 쓰므로 'a'를 붙이지 않습니다.
잘못된 예: I have to skip coffee today because I'm taking a medicine for my stomach.
올바른 예: I have to skip coffee today because I'm taking medicine for my stomach.