I am not a doctor and I'm not giving you medical advice, but this has been my experience.
Debrox does contain carbamide peroxide as the other product mentioned above.
I have had good results by doing this:
4-5 drops in the ear keep head tilted so it doesn't run out for 15 minutes.
Then use that little bulb, filled with warm water, it takes a little doing to fill it, then blast that into your ear. Several times if needed.
If that doesn't work ( not suggesting you do this because there would be a potential to perforate your eardrum ) push the water filled bulb into the wax to try to get behind it and then flush it out, usually comes out in a disgusting lump for me.
I was amazed the first time they did this at the doctors office, they used a large syringe filled with water and kept blasting it under high pressure until it came out, it was slightly painful and sounded like a 747 taking off in my ear, made me dizzy. But it worked.
So this softens it first then you can blast it out and based on my experience I don't think you can damage your eardrum with the bulb.
But again not a doctor and this is just a story of my use of Debrox.