Is it true that steroid nasal spray can cause bones diseases and weakness?

Not really: All medications that contain cortisone like steroids have a label required by fda to mention that they "may" effect eyes, bones, growth, adrenal gland, etc. The real problem is with steroid pills used for long periods or steroid injections. Steroid nasal sprays are very safe in the recommended dosages. The current available data is reassuring.