My cholesterol meds made me sleep for a month and gain 20 lbs, WHY?

I am staying with someone while I shake off the meds, I take NO OTHER MEDICINE. My weight jumped 20 lbs! My neighbor commented on my gain and seemed genuinely concerned which is strange as I barely know the guy. I will repost this when I get back home with THE NAME OF THE DRUG, my mind is just waking up after 5 days without dosage. I just got the stuff a little over a month ago and never realized what it was doing til the other day AFTER I QUIT TAKING IT. Anyone else experience this?