We have investigated Coulomb and pairing effects by using new empirical formulas including the new coefficients for (p, α) at 17.9 MeV, (p, np) at 22. 3 MeV, and (p, nα) at 24.8 and 28.5 MeV energies. A new formula is obtained by adjusting Levkovskii's original asymmetry parameter formula and also Tel et al. formula for proton-induced reactions. The new coefficients by using least-squares fitting method for the reactions are determined. In addition, the findings of the present study are compared with the available experimental data. © Pleiades Publishing, Ltd., 2010.