For the treatment and maintenance of postprandial blood glucose increases (i.e., diabetes mellitus), alpha (α)-amylase is a well-known therapeutic target. In this paper, we report an initial exploration of the work, i.e., in vitro alpha-amylase activity of the hydroalcoholic polyherbal extract of the selected plants. After drying, the plant material is ground individually, and at least 100 gm of the crude powder is prepared from each plant. 100 gm of each plant was combined, and a total of 500 gm of the crude powder (Ichnocarpus frutescens (100 gm) + Ficus dalhousie (100 gm) + Crateva magna (100 gm) + Alpinia galangal (100 gm) + Swertia chirata (100 gm)) was prepared to carry out the extraction. This obtained extract was subjected to preliminary phytochemical screening and in vitro alpha-amylase activity. At 16 mg/mL, acarbose displayed 78.40 ± 0.36% inhibition, whereas the extract exhibited 72.96 ± 0.70% inhibition, which is significantly comparable. The IC50 value of acarbose was 12.9 ± 1.12, whereas the extract exhibited 13.31 ± 1.12 mg/mL. The extract possesses numerous classes of chemicals such as alkaloids, glycosides, tannins, polyphenols, and terpenoids, which can contribute to the antidiabetic activity through alpha-amylase inhibition. This was an initial exploration of the work as a proof of concept for the development of polyherbal tea bag formulation for the treatment of diabetes. In the future, we are aiming to investigate the effectiveness of polyherbal tea bags in the treatment of diabetes using more in vitro and in vivo models. From the present investigation, we have concluded that this extract can be used for the treatment of diabetes.