Happy Pets Inc has had a virtual monopoly for antidepressant drugs for animals for many years (similiar to Eli Lilly's product Prozac for humans). With a patent on this drug, it has had very little competition and this drug has been a major source of company revenue and profit. However, the patent will soon expire and other drug-manufacturing firms seem to be preparing to enter the market in competition with Happy Pets. Describe the changes in pricing that are likely as competitors enter this market.