How long does it take for bethanechol to work for gastroparesis?

Here are some ... Theoretically, it's sound and "yes" to bring a hope, but in reality, it would be more "no' than "yes" for it merely stimulates parasympathetic nerve, not to help restore the physical deficiency created by aging, illnesses, and lifestyles. So, ask the doc who suggests its use. Likewise, this drug have been used for bladder with high expectation, but resulting in mixed result at best.