Thanks for your question on Health Care Magic. No stress can not cause costochondritis. Costochondritis is caused by inflammation of rib cartilage. It is mostly due to over use like heavyweight lifting, strenuous exercise, bad postures in sleep etc. So avoid all these things. Apply warm water pad on affected areas. Take painkiller and muscle relaxant drugs. If you are having stress then consult psychiatrist and get done counseling sessions. Try to identify stressor in your life and start working on its solution. You may need anxiolytic drugs too. Don t worry, you will be alright. Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.