ADHD and OCD are not actually related but ADHD and OCD are what you could call strange bedfellows.
Some people who do have ADHD may also have OCD and they are somewhat similar in how they affect the person and their brain.
The ADHD and OCD are somewhat relatives to each other but not entirely related.
Both ADHD and OCD are caused by problems in the persons frontal lobe but ADHD is caused by under activity in the brain and OCD is caused by over activity in the brain.
So they are similar but entirely the same.
ADHD is considered to be a mental illness just Like OCD.
ADHD is a mental illness that some people have and the ADHD mental illness affects the way a person focuses on things and acts.
Someone with ADHD has a harder time focusing on things than someone who does not have ADHD.
ADHD which is a mental illness can last into adulthood although it's most commonly diagnosed in school aged children.
If a child is having a lot of trouble focusing on something such as in school studying and loses focus often then they may have ADHD.
ADHD medicine can help regain the child's focus and attention on things but should not be taken lightly.