I read your question carefully and I understand your concern. I must say I don t really understand why you have side effects of Aspirin as a title, aspirin doesn t seem to be involved in your situation. Anyway, in theory every company which is approved to have a drug in the market should have undergone strict controls which should guarantee it respects certain standards. There can be some minor differences, but not to the extent which you describe. It is the governmental regulating authorities which should make sure of that, so the pharmacist can t be blamed if the drug is indeed Losartan/Hydrochlorothiazide. However you should discuss with your doctor the possibility of other possible causes for your symptoms, some routine blood tests are indicated in my opinion, kidney function tests in particular.