Help with ADHD and safety!

My husband has severe ADHD.  While this makes him the "fun outgoing one" it is the most frustrating thing to me and is only seeming to get worse.  The "drop and go" messy, unorganized way he is, the leaves cabinets and drawers open, zones out on computer games is SO frustrating but safety issues are now the biggest problem.  We have twin 4 year olds and my son is on the autism spectrum, sensory seeking, and no safety awareness.  I have told my SO countless times he has to keep things picked up like we have an infant that can climb anything because our son will put everything in his mouth and will take anything off of a counter.  It is so stressful and frustrating that I can't rely on him to do this.  I can never relax or trust him alone with the twins and do "sweeps" of my house every night and morning before I leave.  Yesterday he left a pair of sharp scissors on our nightstand and I asked him to put them away before he got in bed....after a reminder when he was getting in bed...he takes them to the kitchen and just lays them down on top of a toy my son plays with!  I wouldn't have know if I didn't get up after him to check....I'm so tired of being so stressed out and feeling like I'm married to a child at times.  The doors get left open (my son is a runner), stove gets left on, scissors and knives on the counter....When I complain and really try to do it nicely he tells me to go take some alone time and go work out, etc. but doesn't understand I can't relax leaving them with him! He wont take medicine because he says it changes his personality too much to be good at his job and turns it around on me when I tell him I can't keep living like this.  Any advice on what to do????