I took Losartan at a very low dose (12.5 mg per day) for 1 year with no side effects whatsoever but then had to use a different pharmacy because of insurance. The new pharmacy (CVS) filled my Losartan prescription with a pill that looked different and was made by a different company. Just a couple of weeks after starting this new pill I started having some mild fatigue and moderate shortness of breath with a cough. I called my GP and they said that it was unlikely that it was the Losartan. I took myself off of the Losartan (since I am only mildly hypertensive anyway) and all these side effects went away. I made an appointment with my GP and he decided to take me off of the Losartan. He said that all generic drugs have to have the same active ingredient but the filler can be different. He said that I was probably allergic or intolerant to one of the fillers. Has your Losartan pill changed?