Could Weight Gain Be Due To Ezetimibe?

My husband started taking Ezetimibe about 1 year ago and retired at the same time. He gained around 30 lbs. and has been on a low carb diet for almost 2 months and has not lost any of the extra weight he gained. I have followed the same diet and lost 17 lbs. so we are very concerned the medication may have something to do with this? He is also on other medication such as Valsartan, Enteric, Metoprolol and Simvastatin.