Medicaid & prescription drug coverage
Who qualifies, what drugs are covered, how to apply, the Medicaid Drug Rebate Program, preferred drug lists, prior authorisation, and what to do when a drug is denied.
What is Medicaid?
Medicaid is the joint federal–state health insurance program for low-income individuals and families in the United States. Established in 1965 under Title XIX of the Social Security Act, it is the largest source of health coverage in the US — covering over 90 million people as of 2026, including 1 in 3 American children. Medicaid is administered by individual states within federal guidelines set by the Centers for Medicare & Medicaid Services (CMS) ↗.
Unlike Medicare (which is federally administered and primarily for people 65+), Medicaid eligibility is income- and category-based. The Affordable Care Act (ACA) Medicaid expansion ↗ extended coverage to adults aged 19–64 with incomes up to 138% of the federal poverty level (FPL) in participating states — though 12 states had not expanded as of October 2026.
Prescription drug coverage is a mandatory benefit for most Medicaid enrollees. States must cover outpatient drugs from manufacturers enrolled in the Medicaid Drug Rebate Program (MDRP) ↗.
Medicaid eligibility: who qualifies?
Federal law requires states to cover certain mandatory groups. States may also cover optional groups. The ACA expansion added a new mandatory adult group in expansion states.
| Group | Income threshold (federal minimum) | Key notes |
|---|---|---|
| ACA expansion adults | ≤138% FPL (≈$20,783/yr individual, 2026) | Only in the 41 expansion states + DC; includes childless adults |
| Children (Medicaid) | Up to 138–200% FPL depending on state/age | Infants 0–1 and children 1–5 covered up to 133% FPL federally |
| Children (CHIP) | Up to 200–300% FPL (varies by state) | Families above Medicaid threshold; separate CHIP or Medicaid expansion |
| Pregnant women | ≥138% FPL (federal minimum); many states higher | Coverage begins day 1; some states extend 12 months postpartum |
| SSI recipients | Automatic (tied to SSI eligibility) | Federally determined; some states use different criteria (209(b) states) |
| Aged, blind, or disabled (non-SSI) | Varies; generally ≤100% FPL + asset tests | Apply through state agency; 90-day determination window for disability |
| Former foster care youth | Up to age 26, regardless of income | Mandatory in all states under ACA; no income test |
FPL = Federal Poverty Level. 2026 FPL: $15,060 (individual), $20,440 (2 people), $31,200 (4 people). Healthcare.gov FPL calculator ↗
How to apply for Medicaid
Choose your application channel
Healthcare.gov ↗ offers a single streamlined application covering Medicaid, CHIP, and ACA Marketplace plans. Your state Medicaid agency ↗ may also have a direct online portal, phone line, or in-person option. Community health centres and navigator organisations can assist with the application for free.
Gather required documents
Most states require:
- Identity: driver's licence, state ID, passport, or birth certificate
- Residency: utility bill, lease agreement, or bank statement
- Income: recent pay stubs, W-2 or 1099 form, or tax return; self-employment records
- Immigration/citizenship: Social Security card, green card, visa documentation
- Household composition: information about everyone in your household
- Existing insurance: details of any current health coverage
Submit and await determination
Most states determine Medicaid eligibility within 45 days (90 days for disability-based applications). Some states provide presumptive eligibility — allowing healthcare providers to temporarily enrol people while the formal application is pending, so coverage begins immediately. If approved, you will receive a Medicaid card or plan information.
Enrol in a managed care plan (if applicable)
Most states use Medicaid managed care organisations (MCOs) ↗. Once approved, you choose a plan from participating MCOs in your area — each with its own formulary (preferred drug list), network of pharmacies, and prior authorisation processes. You may be auto-assigned a plan if you do not choose within the required timeframe.
How Medicaid prescription drug coverage works
Preferred Drug List (PDL)
Every state Medicaid program maintains a Preferred Drug List (PDL) — a formulary of drugs approved for coverage, managed by a Pharmacy & Therapeutics (P&T) Committee. PDL drugs have the lowest cost-sharing for beneficiaries. Non-PDL drugs typically require prior authorisation (PA). States negotiate supplemental rebates with manufacturers to place drugs on the PDL — meaning cost-effectiveness and rebate offers drive formulary placement, not clinical need alone.
The six federally protected drug classes must be covered without restriction in all states:
All other drug classes may be managed via prior authorisation, step therapy, or quantity limits.
Prior Authorisation (PA)
Prior authorisation requires prescribers to obtain plan approval before a drug is covered. PA criteria typically include: clinical necessity documentation, failure of a preferred (usually cheaper) alternative ("step therapy"), diagnosis confirmation, and quantitative prescribing limits. CMS PA guidelines ↗ require states to respond to PA requests within 24 hours for urgent cases and 72 hours for routine requests. If PA is denied, prescribers can appeal — see the appeals section below.
340B Drug Pricing Program
Safety-net providers (federally qualified health centres, Ryan White HIV/AIDS programme sites, children's hospitals) can access 340B drug pricing ↗ — purchasing covered outpatient drugs at significantly reduced prices (up to 50% discount from manufacturers). Patients served by 340B-covered entities can access these savings even when paying out-of-pocket. Many Medicaid beneficiaries receive care at 340B-covered providers.
Medicaid Drug Rebate Program (MDRP)
The MDRP is the mechanism by which pharmaceutical manufacturers pay quarterly rebates to state and federal Medicaid programs in exchange for Medicaid coverage of their drugs. Established in 1990, it is the most significant drug pricing programme in the US by dollar value — saving Medicaid an estimated $40+ billion annually.
Basic rebate — brand drugs
Or the difference between AMP and Best Price — whichever is greater. Best Price = lowest price sold to any US commercial customer.
Basic rebate — generics
Generic manufacturers pay a lower base rebate rate reflecting their thinner margins and competition from multiple generic entrants.
Inflation rebates
Added by the Inflation Reduction Act (2022) ↗. If a manufacturer raises AMP faster than CPI-U, they must pay the difference as an additional rebate — eliminating the financial incentive for excessive price hikes.
Supplemental rebates
States negotiate additional rebates with manufacturers to achieve PDL placement. Supplemental rebates are state-retained and can be substantial — reducing net drug costs to the state by 40–70% for preferred agents.
For clinicians prescribing to Medicaid patients: generics are strongly preferred on PDLs. Prescribing a brand drug when a therapeutic generic exists almost always requires prior authorisation.
What to do if a drug is denied
Request the denial letter — it must specify the reason (not on formulary, PA required, step therapy, quantity limit exceeded). This determines the correct appeal pathway.
Your prescriber submits PA documentation — clinical records showing medical necessity, failed alternatives (if step therapy required), and diagnosis codes. Many states allow PA requests via electronic prescribing systems.
You have the right to appeal any Medicaid coverage decision. File a State Fair Hearing request within the timeframe stated in the denial notice (typically 90 days). For urgent situations, request an expedited appeal — states must respond within 72 hours. The CMS appeals overview ↗ explains the process.
If a drug remains unavailable through Medicaid, many manufacturers offer patient assistance programmes (PAPs) ↗. Websites like RxAssist ↗ and NeedyMeds ↗ list manufacturer and non-profit drug assistance programmes by medication name.
Dual eligible: Medicaid + Medicare Part D
People who qualify for both Medicaid and Medicare are called "dual eligible." As of 2026, approximately 12 million Americans are dually enrolled. For prescription drug coverage, dual-eligible individuals receive their drugs through Medicare Part D (not Medicaid), with Medicaid paying the cost-sharing (premiums, copays, deductibles). They are automatically enrolled in Low Income Subsidy (LIS/"Extra Help") — eliminating most out-of-pocket drug costs.
Dual-eligible individuals are often the sickest and most complex patients — they use high-alert medications requiring careful monitoring (immunosuppressants, anticoagulants, antipsychotics) and benefit from coordinated care. The CMS Medicare-Medicaid Coordination Office ↗ oversees integrated dual-eligible programmes.