How do I become an Ohio medical marijuana Caregiver? Registry Identification Cards: All patients and caregivers wishing to obtain medical marijuana must receive a state-issued medical marijuana patient ID card. Caregiver Eligibility: Individuals 21 and older can serve as a caregiver for no more than two medical marijuana patients. Each patient can have up to two caregivers. Patient and Caregiver Registration: The recommending physician, or a physician delegate, must submit the caregiver and patient’s name to the Ohio Board of Pharmacy medical marijuana patient and caregiver registry following their recommendation for medical marijuana. Registration Fees: The annual registration fee for a patient is $50. The registration fee for caregivers is $25. Veterans receive a 50% discount on this registration fee. Minors: Patients under the age of 18 are required to have a parent or legal representative serve as their caregiver.