Reference, not legal or medical advice. Statutes change. Every section below carries a last-verified date and a primary-source citation. Verify against current statute and consult a licensed pharmacist or attorney for any decision with legal or health consequences.
Prescription Drug Law · Texas (TX)

Prescription Drug Law in Texas: 2026 Reference

Last verified 2026-05-23 · Texas (TX)
By Vincent Couey, RxGrab editor.

Texas, Rx posture at a glance

Four axes from current statute and agency guidance. Teal bar = substitution/assistance/access in place; amber = permissive or absent.

Generic substitution Mandatory by statute State assistance (SPAP) No broad SPAP 90-day fill allowed Allowed PMP prescriber query Required by statute

At a glance: Texas Rx rules

Generic substitution mandateMandatory by statute
State Pharmaceutical Assistance ProgramNo broad SPAP
90-day fills permittedAllowed
PMP mandatory prescriber queryRequired by statute

Generic substitution law Verified 2026-05-23

Texas mandates generic substitution by default. Under Texas Occupations Code Chapter 562 and Texas State Board of Pharmacy rules, a pharmacist shall substitute a generically equivalent drug unless the prescriber indicates "Brand Necessary" or "Brand Medically Necessary" in the prescriber's own handwriting (or by equivalent electronic flag for e-prescriptions). Patient consent is not separately required, but pharmacists must notify the patient of substitution and price differential.

Medicaid formulary access Verified 2026-05-23

The Texas Vendor Drug Program (VDP) administers Medicaid pharmacy benefits and maintains the state Preferred Drug List (PDL). Non-preferred drugs require prior authorization initiated by the prescriber. Most Medicaid members receive pharmacy benefits through managed-care organizations (STAR, STAR+PLUS, STAR Health, STAR Kids) which must cover all VDP formulary drugs but may apply their own utilization management on non-preferred agents.

Preferred Drug List: View current PDL

Prior authorization contact: Texas Vendor Drug Program PA: 1-877-728-3927

State Pharmaceutical Assistance Verified 2026-05-23

Texas does not run a Medicare-recognized broad SPAP. The state operates the Kidney Health Care Program (KHC) for ESRD patients which covers drugs related to dialysis and transplant. Low-income Texans needing general drug-cost help route through Medicaid (if eligible), federal Extra Help for Medicare Part D, the Texas Health Information, Counseling, and Advocacy Program (HICAP equivalent), and manufacturer Patient Assistance Programs.

Eligibility: Texas operates the narrow Kidney Health Care Program (KHC) for end-stage renal disease drug coverage; no broad SPAP.

Dispensing rules: 90-day fills, mail order, refills Verified 2026-05-23

Texas permits 90-day fills of non-controlled chronic medications at retail or mail-order pharmacies. Out-of-state pharmacies dispensing into Texas must be licensed as Class E Nonresident Pharmacies by the Texas State Board of Pharmacy. Refill-too-soon thresholds are plan-set, typically 75% for non-controlled drugs. Schedule II controlled substances require a new prescription each fill; Schedule III-V refills up to 5 within 6 months per federal CSA.

Prescription Monitoring Program Verified 2026-05-23

The Texas Prescription Monitoring Program is administered by the State Board of Pharmacy. Under Health & Safety Code ยง 481.0764, prescribers must check the PMP before issuing the first prescription of a Schedule II opioid, benzodiazepine, barbiturate, or carisoprodol to a patient. Pharmacists must report dispensing within one business day.

PMP portal: Texas Prescription Monitoring Program (PMP Aware)

340B drug pricing program Verified 2026-05-23

Texas hosts a large 340B network including FQHCs, Ryan White clinics, MD Anderson and other DSH hospitals, and rural critical-access hospitals. Texans without insurance or with high deductibles may access steeply discounted drugs by establishing care with a 340B covered entity. Filter the HRSA OPAIS database to Texas to locate a participating clinic in your area.

Find a 340B clinic in Texas: HRSA OPAIS database (TX filter)

Need patient assistance beyond Texas Medicaid?

Our sister site OmniRx maintains a federal-side patient assistance program directory covering manufacturer PAPs, foundation copay assistance, GoodRx-style discount cards, and 340B locators applicable nationwide.

Open the OmniRx assistance directory →

Compare Texas pharmacy prices

Once the law side is clear, the next question is which pharmacy actually has the cheapest fill. Use the RxGrab Pharmacy Finder to compare CostPlus Drugs, Costco, Walmart, Amazon Pharmacy, and other discount pharmacies on your specific medication, and read our generic vs brand explainer for the bioequivalence rules behind every substitution.

FAQs about prescription drug law in Texas

Can my Texas pharmacist swap my brand-name drug for a generic?

Yes, by default they must, unless your prescriber wrote "Brand Necessary" or "Brand Medically Necessary" in their own handwriting (or its electronic equivalent). Texas Occupations Code Chapter 562 makes generic substitution the default rule.

Why does my Texas Medicaid pharmacy benefit need prior authorization?

Texas Vendor Drug Program maintains a Preferred Drug List. Non-preferred drugs require the prescriber to submit a prior authorization request, call 1-877-728-3927 to start. Managed-care plans (STAR, STAR+PLUS, etc.) must cover all VDP-listed drugs.

Does Texas have a state drug-assistance program for seniors?

No broad SPAP. Texas operates the narrow Kidney Health Care Program for ESRD. For general help, Medicare seniors should apply for federal Extra Help; non-Medicare residents should check Medicaid eligibility or use manufacturer Patient Assistance Programs.

Can out-of-state pharmacies mail prescriptions to Texas?

Yes if they hold a Class E Nonresident Pharmacy license from the Texas State Board of Pharmacy. Major mail-order pharmacies (Cost Plus Drugs, Express Scripts, OptumRx, Amazon Pharmacy) maintain this license.