Vasicinol is an alkaloid compound found in the plant Adhatoda vasica (commonly known as Malabar nut or Vasaka), which has a long history of use in traditional medicine systems such as Ayurveda for the treatment of respiratory conditions including cough and asthma. Scientifically, vasicinol and related alkaloids (such as vasicine and vasicinone) have been shown in preclinical studies to possess bronchodilatory and expectorant properties. These effects are believed to be mediated through inhibition of bronchial smooth muscle contraction and enhancement of mucociliary clearance in the respiratory tract.

Several animal studies have demonstrated that vasicinol and its analogs can reduce spasms in the airway, supporting its potential use in spastic (or spasmodic) cough. Additionally, extracts containing vasicinol are reported to have antitussive (cough-suppressing) effects in experimental models. Some limited clinical studies and case reports in humans also indicate beneficial effects of Adhatoda vasica preparations in patients with cough and bronchitis, although most studies involve the whole plant extract rather than isolated vasicinol.

Despite these promising findings, large-scale, high-quality human clinical trials specifically evaluating isolated vasicinol for spastic cough are lacking. Therefore, while the mechanistic and preliminary clinical evidence is supportive, the overall scientific evidence is moderate and further research is warranted to establish efficacy and safety in humans.