“…These similarly inhibit 5-HT 3 receptors, with IC 50 values close to plasma concentrations, and antagonize 5-HT 3 receptor-mediated gut contractions Kelley et al, 2014). Strategies to find analogous drugs (e.g., phenoxypropoxybiguanides) may therefore wish to consider their effects on 5-HT 3 receptors as an indication of gut intolerance earlier in their development (Shearer et al, 2005;Zucca et al, 2013). It is also noteworthy that the first-line antidiabetic drug metformin (Bolamyn, Glucophage) is also a biguanide, as are the related antidiabetics phenformin and buformin.…”