What is your first line treatment for a patient with epilepsy who is homeless and has a history of poor adherence?

It is likely an indication of my being old school, but if a homeless person needs medication they can’t afford and will take only intermittently, I would suggest phenobarbital. In spite of cognitive and other issues, in this situation, it is inexpensive, has a very long half-life, so withdrawal and skipped doses are less harmful and it’s once-a-day dosing and needs no lab monitoring for toxicity.

That's definitely a challenge. You need to try to assess what access they might have, such as a pharmacy nearby their usual haunts and what they can /are willing to afford. We had an access clinic at one of the local shelters that had a limited formulary supported by the college of pharmacy which stocked a limited number of meds. The homeless there had a consistent clinic day on site for follow-up, although labs couldn't be done there. PAP programs often require a deliverable address. You don't want to use something that requires a challenging titration or where stopping/starting suddenly will result in DRESS or similar issues. Motivation is key. Phenytoin is inexpensive & widely available and can be given on a once-daily basis, which is about the best scenario to support success. Zonisamide may be useful for generalized seizures and can be found inexpensively at some pharmacies. GoodRx and the $10 lists for Walmart, Target & grocery stores may be useful. Needy Meds website will direct you to the PAP forms. Scheduled substances are to be avoided. Pills get stolen regularly. I had an alcoholic patient who was homeless & also migratory. He was on meds (he did have Medicaid) and had previously been implanted with a VNS, and there was an increase in ER visit frequency when the generator reached end of life, so our surgeon kindly replaced it during an acute hospitalization. This helped, but if your patient has addiction issues (alcohol, tobacco, cannabis, etc) these will typically take precedence. Follow-up is typically spotty since transportation to clinic is also hard. Sorry to be a negative voice, but it's a tough situation. Be persistent!