A medicinal product used for gargling/mouth rinsing (mouthwash). Often used in written or medical contexts; synonymous with うがい薬.
風邪の予防として、病院で含嗽剤を処方された。
As a cold prevention measure, I was prescribed a mouthwash at the clinic.
市販の含嗽剤には殺菌成分が含まれているものが多い。
Many over-the-counter mouthwashes contain antiseptic ingredients.