OCD is a form of anxiety, and stimulant medications can increase anxiety, especially if the dose is too high for that individual.
There are two types of stimulants used to treat ADHD — amphetamines (like Vyvanse) and methylphenidates (Ritalin, Concerta). Since the majority of individuals do better on one type or the other but not both, I’d consider trying a methylphenidate. I’ve read many times that amphetamines often increase anxiety more.
Many individuals with ADHD have co-existing conditions, including OCD. Many take more than one medication to address more than one condition. Here’s more on treating OCD:
ADDitude Community Moderator, Author & Mentor on Parenting ADHD, Mom to teen w/ ADHD, LDs, and autism