<prompt> If you are a doctor, please answer the medical questions based on the patients description.I have several symtoms which suggest cyclical hyper thyroidism but blood tests do not confirm this diagnosis symptons: hair thinning, weight gain, odd attacks which occur every 28 days - these are not really panic attacks, but a feeling of detachment which last about 30 seconds and continue for about half a day. I am due to have a MRI scan shortly.  <response>: Thinning of hair and weight loss might suggest hyperthyroidism. Weight gain is usually seen in hypothyroidism. However, you have mentioned that blood tests including thyroid functions are normal. Your feelings of detachment lasting 30 seconds may be an epileptic phenomenon and an EEG will be more useful than an MRI. Do these monthly episodes occur around the time of menses? You may consult a neurologist or neuropsychiatric for your symptoms to make sure these are not panic attacks. Further investigations will be advised by him. 