Hello doctor I was prescribed sodium cromoglycate 2% eye drops. The doctor ticked the box brand substitution not permitted. I asked at the counter that I have never had generic products. As a result I was dispensed a generic opticrom but I have noticed it later when I started to use it. I experience burning sensation and irritation to my eyes. What are my consumer rights in this case? Does the pharmacist rectify her mistake and give me a brand product? Thank you for your time and looking forward for your reply.