How to Help Your Patients Find Prevalite in Stock: A Provider's Guide

If you're a primary care physician, cardiologist, gastroenterologist, or NP/PA who prescribes cholestyramine (formerly Prevalite), you may already be fielding calls from patients who can't find it at their pharmacy. This guide gives you practical, actionable steps to help your patients maintain access to this medication — while minimizing disruptions to your practice workflow.

First: What's the Current Situation with Cholestyramine?

The Prevalite brand has been discontinued; all cholestyramine is now generic. As of early 2026, generic cholestyramine is experiencing intermittent supply disruptions. Stock varies significantly by pharmacy and region. For the full clinical briefing, see our

Prevalite shortage briefing for providers.

Step 1: Update Your Prescription to Allow Generic Substitution for Both Formulations

Ensure your prescriptions allow generic substitution and specifically mention that both the regular and light (sugar-free) formulations are acceptable. These are therapeutically equivalent — both deliver 4g of anhydrous cholestyramine resin per dose. When one formulation is unavailable, the other may be in stock.

Exception: Do not use the light (aspartame-containing) formulation in patients with phenylketonuria (PKU).

Step 2: Prescribe a 90-Day Supply When Possible

Prescribing 90-day supplies reduces the frequency with which patients must locate the medication and refill during a shortage period. Most insurance plans accommodate 90-day fills for maintenance medications like cholestyramine, often at reduced copays through mail-order pharmacies. Encourage patients to request 90-day fills whenever supply is found.

Step 3: Direct Patients to medfinder

medfinder is a service that contacts pharmacies in a patient's area by phone to check which ones have their medication in stock. Patients provide their medication, dosage, and zip code. medfinder does the calling and texts results directly to the patient. This is especially helpful for patients who are elderly, disabled, or simply don't have time to call multiple pharmacies. Direct patients to

medfinder.com or include the website in your patient handout materials.

Step 4: Have a Standing Alternative Ready for High-Risk Patients

Identify patients for whom a gap in cholestyramine therapy would cause significant harm — particularly those using it for bile acid diarrhea or refractory pruritus. For these patients, have a contingency prescription ready or discuss the plan proactively:

• Bile acid diarrhea: Colesevelam (Welchol) 1.875g twice daily or 3.75g once daily is a well-supported alternative. Generic available.
• High cholesterol: Colesevelam, colestipol, ezetimibe, or a statin may all be appropriate depending on patient history and tolerability.
• Pruritus from biliary obstruction: Colesevelam or colestipol; coordinate with GI/hepatology for more complex cases.

Step 5: Address Insurance Barriers to Alternatives

If you need to transition a patient to colesevelam or colestipol, be prepared for potential prior authorization requests. Colesevelam is typically on a higher formulary tier than generic cholestyramine. Document the shortage situation in your medical notes — most plans will process shortage-based prior authorizations efficiently. Use language like: "Patient is unable to obtain generic cholestyramine due to documented regional shortage. Requesting coverage of colesevelam as clinically equivalent alternative."

Step 6: Monitor Drug Interactions When Cholestyramine Is Stopped

Cholestyramine significantly reduces absorption of warfarin, levothyroxine, digoxin, fat-soluble vitamins, mycophenolate, and raloxifene. When cholestyramine is discontinued — even temporarily — bioavailability of co-medications may increase. Schedule appropriate monitoring:

• Warfarin: Check INR within 1-2 weeks of stopping cholestyramine.
• Levothyroxine: Recheck TSH 6-8 weeks after stopping cholestyramine.
• Digoxin: Monitor levels and clinical response in the week following discontinuation.

Sample Patient Communication Script

If you need to communicate with patients about the shortage, here is a sample message for your patient portal:

"We are aware that some pharmacies are currently having difficulty stocking cholestyramine (previously known as Prevalite). If your pharmacy is out of stock, please: (1) ask your pharmacist about the "light" formulation, (2) try a different pharmacy, (3) use medfinder.com to locate a pharmacy near you that has it in stock. If you are unable to find it and are experiencing symptoms, please call our office so we can discuss alternatives."