Formulation and Evaluation of Polyherbal Antiasthmatic Cough Syrup

This study developed and evaluated a polyherbal anti-asthmatic cough syrup using Glycyrrhiza glabra, Withania somnifera, Cinnamomum verum and Bauhinia racemosa. These plants were chosen for their documented anti-asthmatic, anti-inflammatory, mucolytic, antioxidant, and antimicrobial effects. Extraction was carried out by Soxhlet method with ethanol for Withania somnifera and Cinnamomum verum, while Bauhinia racemosa and Glycyrrhiza glabra were extracted by cold maceration using ethanol and distilled water, respectively. The extracts were concentrated into semi-solid residues for formulation. Phytochemical analysis confirmed the presence of Quercetin in Bauhinia racemosa, Glycyrrhizin in Glycyrrhiza glabra, and Cinnamaldehyde in Cinnamomum verum. UV-visible spectroscopy verified extract purity, with maximum absorbance values matching reported standards and calibration curves showing strong linearity, confirming reliability of the method. FTIR spectroscopy and DSC indicated no significant interaction between extracts and excipients, establishing stability of the formulation. Three formulations were developed and tested, among which the third formulation was most compliant with Indian Pharmacopoeial standards. Each 10 milliliters contained Bauhinia racemosa 100 milligrams, Cinnamomum verum 100 milligrams, Withania somnifera 200 milligrams, and Glycyrrhiza glabra 200 milligrams in a sugar syrup base with preservatives. The formulation showed significant pharmacological activity. Anti-inflammatory testing revealed 65 to 74 percent inhibition, with Glycyrrhiza glabra reaching 87.4 percent, comparable to diclofenac sodium. Antioxidant activity was highest in Withania somnifera at 88.3 percent, while the syrup demonstrated 59 to 65 percent inhibition. Antibacterial testing showed Cinnamomum verum with the strongest effect at 18.7 millimeters of inhibition, followed by Bauhinia racemosa at 9.8 millimeters, and the formulation at 8.2 millimeters against Klebsiella pneumoniae. Ex- vivo studies on goat trachea showed that the syrup inhibited 77.3 percent of histamine-induced contraction, confirming bronchodilatory and antihistaminic potential. Overall, the formulation demonstrated strong anti-inflammatory, antioxidant, antimicrobial, and bronchodilatory effects, supporting its use as an anti-asthmatic cough syrup.