There is a trademarked product used in therapy that is used to increase breathing capacity. I would like to use that product in a kit with protocols and instructions that would improve its current use and expand its uses. How do I do that without infringing on the trademark or being limited by the trademark owners?
You can onsell and repackage products, including products subject to trademarks and patents. Simply identify the original trademark within your package.
For example: OreoTM Cookie McFlurryTM. Oreo is TM Mondelēz International, McFlurry is TM McDonalds.