In the United States, the Food and Drug Administration rules require that safety and efficacy of all medicines must be proved before they are approved for use. Hence an equivalent of Waterburys compounds (Red or any label) is not permitted.
Grilinctus BM is a combination of two drugs: terbutaline (anti asthmatic) and bromhexine (claimed to be a mucus thinner). Bromhexine is not approved for use in America. Terbutaline alone is marketed under the trade name of Brethine by aaiPharma. Even if bromhexine was approved, unlike India, combination products are not approved in the United States unless sound scientific reasons are given. In India many combination products are being marketed without central government approval.