Medication Adherence Calls With AI Voice Agents: Who to Call, What to Ask, When to Escalate

A medication adherence call is a short outbound check-in that asks a patient whether they are taking a medication as prescribed, finds out what is getting in the way if they are not, and routes anything clinical, such as a side effect, to a pharmacist or nurse. An AI voice agent can place these calls at scale, as long as it stays on operational questions and the escalation paths are built before the first call.

Pharmacies, health plans and care management teams usually know who needs a check-in. The limit is staff time: a pharmacist dialing and leaving voicemails is not reviewing the patients who need clinical attention.

Which patients should get an adherence call, and when?

Tie every call to an event in your own data, not to a calendar blast. Your clinical team sets the timing for each trigger.

The refill itself is a separate workflow. When a patient says "I need a refill," hand them to your refill intake, which the pharmacy refill calls page covers, including outreach to overdue patients.

What should the agent ask on an adherence check-in?

A fixed sequence of short questions, each with an answer you can record:

1. Confirm identity. Ask for the details your policy requires, such as full name and date of birth, before the medication is named. If someone else answers, ask for a good time to reach the patient and say nothing about the medication.
2. State the purpose. "I'm calling from your pharmacy to see how things are going with a medication you started recently."
3. Ask about adherence so that "no" is easy to say. "Some people miss doses now and then. Over the past week, have you been able to take it the way it was prescribed?"
4. If not, ask why. Record one reason: forgot, ran out, cost, side effects, unsure how to take it, stopped on purpose, or other.
5. Ask about side effects or new symptoms. Keep it open. Any answer other than "no" gets escalated. The agent records what the patient said and does not judge it.
6. Check supply. If they are close to running out, route them to the refill intake.
7. Close. Give the pharmacy number and when the next check-in will happen.

Pass patient details in as dynamic variables. In a Retell batch call, every non-reserved CSV column becomes one, such as {{medication_name}}; through the Create Phone Call API they go in retell_llm_dynamic_variables. A metadata field carries your record ID so results map back to the right patient.

Medication names are where calls break. Add each one to the agent's pronunciation dictionary (IPA works on Retell platform voices and several providers) so the agent says it correctly, and to boosted keywords so transcription is more likely to catch it.

What must the agent never answer?

Anything that needs clinical judgment. Write the boundary into the prompt as a list, not a principle:

• Whether to skip, double, stop or restart a dose
• Whether a symptom is a side effect, or whether it is serious
• Interactions with other medications, alcohol or food
• Any change to dose or timing

For each one, the agent says a pharmacist or nurse will help, and escalates. Two settings back up the prompt. Retell's output guardrail for regulated_professional_advice, which covers medical advice, replaces a flagged response with a placeholder before it is spoken; it does not transfer the call, so the escalation rule stays in the prompt. A knowledge base limited to approved operational answers, such as hours, locations and how refills work, keeps the agent from improvising.

Write an emergency rule with your clinical team: which symptoms or words trigger it, the exact instruction the agent gives, such as calling 911, and what happens to the call next. Test it before launch.

How do side effects and clinical questions reach a pharmacist or nurse?

Live or queued, chosen by urgency and by whether someone is available.

Post-call functions run after Post Call Extraction, so they can read your custom fields. Prebuilt tools cover HubSpot, Salesforce, Microsoft Dynamics 365, GoHighLevel, Zoho CRM and Zendesk. Retell has no prebuilt EHR or pharmacy system connector, so writing into one goes through a custom function against your API or interface engine; the EHR connection guide covers the options, and the guide to how call transfers work covers the live handoff.

Give the queue an owner, and let the agent promise only a callback time your team can meet.

What happens when the agent reaches voicemail or a family member?

Leave as little as possible. Retell detects voicemail in the first three minutes of an outbound call, and the agent either hangs up or leaves a message. Use a static sentence that names no medication or condition, for example "Hi {{first_name}}, this is your pharmacy calling with a routine follow-up. Please call us back at [number]." Agree on the wording with your privacy officer. These calls end with the reason voicemail_reached, so your system can plan a later attempt.

For family members and caregivers, the identity step does the work: by default, the agent discusses nothing beyond a callback request with anyone but the patient.

Which consent and privacy rules apply to adherence calls?

Both the TCPA and HIPAA, so review the program with counsel. This is general information, not legal advice.

• AI voices count as artificial voices. The FCC has confirmed that calls using AI-generated voices fall under the TCPA's artificial voice rules.
• Residential lines. FCC rules allow a "health care" message made by or on behalf of a HIPAA covered entity or its business associate to a residential line without prior consent, if the caller makes no more than one call per day and three per week to each patient and honors opt-outs.
• Mobile numbers. A non-emergency artificial voice call generally needs the patient's prior express consent. A narrow exemption covers certain healthcare provider calls, including prescription notifications and post-discharge follow-up, only under strict conditions, including: free to the patient, sent to the number the patient provided, one message per day and three per week, an opt-out in each message, and generally one minute or less per voice call. A check-in with several questions can run past a minute, so plan on having consent.
• Opt-outs. Patients can revoke consent by any reasonable method. Turn on do-not-contact handling, and filter flagged contacts out of every batch list, because batch calls do not check the do-not-call flag. The Create Phone Call API checks it when you pass honor_internal_dnc: true.
• Marketing. The HIPAA Privacy Rule's definition of marketing excludes refill reminders and other communications about a drug currently prescribed for the patient, as long as any payment received for making them is reasonably related to the cost. If a third party funds the program, ask counsel how that rule applies.

On the platform side, Retell is HIPAA compliant for handling protected health information, and a signed business associate agreement is required before any PHI goes through Retell. The BAA is self-signed with no fee. Then set each agent's data storage (for example, everything except PII, with names, dates of birth and medical IDs scrubbed), a retention period from one day to two years, and signed recording URLs. The HIPAA guide for AI phone agents and the TCPA guide for outbound AI calls go deeper.

How do you schedule and pace check-ins?

Use one of two documented patterns:

1. A daily batch. Upload the patients whose trigger fired as a batch call with a calling time window. Reserved concurrency keeps slots open for inbound calls, and pace comes from the concurrency you allocate.
2. Event-driven calls. Your system calls the Create Phone Call API when the event happens, such as a first fill or a discharge, with honor_internal_dnc: true.

Retell has no automatic redial, so your system decides when to try again. Count every attempt against the limits that apply, and call within hours your patients expect, in their time zone.

What should you measure in a pilot?

Define extraction fields before the first call, so every connected call produces the same record:

Custom fields stay empty on calls that never connected, so count reach separately. Before going live, build simulation test cases where an AI plays the patient: one reports dizziness, one asks whether to double a missed dose, a family member answers, one mangles the medication name, one says "stop calling." Rerun them as a batch test after every prompt change, then pilot on a small list and have a pharmacist read every escalated call and a sample of the rest.

Launch checklist

• Triggers and timing approved by your clinical team
• Clinical boundary list and emergency rule in the prompt, guardrail on
• Warm transfer number and queued callback owner set
• Voicemail message reviewed by your privacy officer
• Consent checked per number type with counsel; do-not-contact handling on
• BAA signed, storage mode, PII scrubbing and retention set per agent
• Medication names in the pronunciation dictionary and boosted keywords
• Extraction fields defined and test cases passing

Where to start

Pilot one trigger, such as new prescriptions for one condition, before adding more. Retell's AI voice agents for healthcare place the calls, hand clinical questions to your pharmacists and nurses with a private briefing, and write each outcome to the system your team already works from.