I have a typical 10 year old daughter with ODD and every day is a battle. I also have a child with Autism with ODD and ADD, but in my response below I'm more addressing the ODD aspect (so how I handle things with my typical child). My 10 year old does NOT take medication for ODD because there isn't one and it's a personality trait that will actually work in her favor as an adult. It's simply that it's very difficult to parent people with ODD. :-)
Punishment and meds alone aren't going to work with a child with Oppositional Defiance Disorder. It just makes them more defiant. The problem as these children see it is that they are equal to adults in authority and that rules don't apply to them. So when you punish rather than discipline, you have problems.
Discipline must include open discussion. It must include back and forth conversation with turn taking and maintaining your position as the parent and why it's important for house rules to be followed and school rules to be followed. It's going to take repetition and patience. If you have house rules, put them in writing on a board visible for all in the house to see.
1. Everyone is respectful.
2. Everyone does homework.
3. Everyone does chores.
4. Everyone bathes/brushes teeth & hair.
5. Everyone obeys school rules.
6. Obey mom and dad for safety.
7. Everyone tells the truth.
8. Everyone remembers that stealing is wrong.
9. Whatever other house rules you have, but try to limit it to ten. Try to keep from using negative phrasing or they'll literally be compelled to disobey it. Compelled. As in "won't have control and will feel as if they must disobey a rule that tells them 'don't do that."
Then on the rule board make sure you put at the bottom very clearly what the consequences will be for breaking the rules. If rules are broken you can take away a privilege like playing video games one day of the weekend for each incident where rules are broken. You can then also say, "It's not my fault, it's a rule. See? It's in writing."
Also on the board have goals that are being worked toward for the weekend that he can choose from. Have a separate chart where he can earn stickers or checks every time he receives praise for following through with positive behavior. He's going to need a lot of positive reinforcement. Something that worked well was talking about the rules together as a family before writing them down so that we could agree on them all, and then we did the same with the consequences. When the family agrees together, it's much more difficult later to argue that they're unfair.
And whenever possible, you're going to have to practice phrasing things in a way that doesn't sound like you're giving him orders or telling him what to do. He has to believe that he has a choice. "Samuel, I have a couple of chores that need to be done. I need the toys in the living room picked up, but I also need your shoes to be put away. Which would you like to do first?" "Sam, I was thinking that some time after you get dressed for school but before we wait for the bus that you could _____ for me."
So that would also extend to lying and stealing. If he breaks the rules, then you follow the rules of consequence, but try to maintain as much positive language as possible. What you can do now is with the diagnoses that your son has is to request a PPT with the school for an IEP. That means that when your son's behaviors are due to the disorders they'll have a plan in place per the IEP. You will have to request to have him evaluated by the school and they'll give you a questionnaire to fill out and the school psychologist and teachers will do the same. You can include a written letter with the diagnoses and recommendations from your child's doctors due to the diagnoses, especially if he receives therapy such as Cognitive Behavioral therapy.
PPT = Planning and Placement Team which you would be an active member of
IEP = individualized education plan