It depends on your plan:

• Free: Each member can use up to three combined scheduled dose routines and enabled health reading types (counted together—three “slots” per person). There is also a household maximum of twelve such slots across all members so limits cannot be bypassed by adding many profiles. When a limit is reached, the app prompts you to subscribe for unlimited capacity.
• Family Care: No practical cap from these rules—add the routines and readings your care plan needs.

Details and examples sit with the broader subscription FAQ: Subscription — free plan limits.