Limited Distribution Drugs: A Guide to Networks and Specialty Pharmacies

Many medications that treat complex medical conditions are only available through limited distribution. This means you probably can’t just pick them up at your local pharmacy. Instead, you can only get them from specific pharmacies — usually specialty pharmacies.

This can sometimes add a few extra steps when accessing these medications. But it can also allow you to have a closer relationship with your healthcare team. And you may be more likely to take your medication as prescribed. That’s because specialty pharmacies conduct regular follow-ups. This is to answer any questions you have and make sure you’re taking it properly, to help you get the best results.

So, what exactly is a limited distribution drug, and what happens if you’re prescribed one?

What are limited distribution drugs?

Limited distribution drugs (LDD) are medications that are only available through certain pharmacies. They’re generally used to treat complex or rare medical conditions.

LDDs are usually higher cost. They may also have special storage and handling, administration, or monitoring requirements.

Why can you only get limited distribution drugs filled at specific pharmacies?

Most pharmaceutical manufacturers manage some or all of their specialty medications through a limited distribution. This means only some specialty pharmacies are allowed to dispense their LDDs.

It may seem like manufacturers are trying to control access to their medications. But there can be benefits to limiting the pharmacies that dispense LDDs for you, too.

For one, this model ensures that the pharmacy’s clinical staff is highly trained on your medication. They can support you in ways a traditional community pharmacy can’t. 

For example, the staff may be able to give you tips on how to avoid side effects. Side effects can often cause people to stop taking their medication.

They may also be able to handle insurance coverage and billing issues, which can be more complex or take longer with specialty medications. This might include obtaining copay assistance so your medication is more affordable. And dedicated staff will typically conduct regular follow-ups to help you stick to your treatment plan more closely.

What types of medications are limited distribution drugs?

LDDs typically have a higher risk of serious side effects. As mentioned above, they can also be higher cost or have special storage requirements. Some may even require thorough training before you can safely use them. 

Here are some medical conditions with examples of their LDDs:

• Cancer: Keytruda (pembrolizumab), Tarceva (erlotinib), Xtandi (enzalutamide)

• Multiple sclerosis: Aubagio (teriflunomide), Kesimpta (ofatumumab), Plegridy (peginterferon beta-1a)

• Rheumatoid arthritis: Actemra (tocilizumab), Kevzara (sarilumab)

• Psoriasis: Cosentyx (secukinumab), Otezla (apremilast)

Some LDDs are only available through your healthcare provider. These are usually medications that need to be administered by a healthcare professional, such as an infusion.

What are limited distribution networks?

Manufacturers work with a small number of pharmacies to dispense their LDDs. These are called limited distribution networks (LDN). If you’re prescribed an LDD, you may receive it from one of these contracted pharmacies.

What are some examples of pharmacies that offer limited distribution drugs?

Specialty pharmacies are almost always mail-order pharmacies. They have highly trained clinical staff who handle all aspects of your prescription. This includes processing, billing, training, and more.

Some healthcare providers have existing relationships with particular specialty pharmacies. So, they may prefer to send people to those pharmacies. This may occur with certain conditions, such as cancer. 

Accredo, CVS Caremark, and Optum specialty pharmacies are a few of the most common pharmacies that dispense LDDs. Examples of LDDs dispensed by these specialty pharmacies include:

• Accredo specialty pharmacy: Nucala (mepolizumab), Otezla (apremilast), and Orkambi (lumacaftor / ivacaftor)

• CVS/Caremark specialty pharmacy: Actemra (tocilizumab), Camyzos (mavacamten), and Exjade (deferasirox)

• Optum specialty pharmacy: Copiktra (duvelisib), Imbruvica (ibrutinib), Venclexta (venetoclax)

What should you know if you’re prescribed a limited distribution drug?

If you’re prescribed an LDD, your insurance provider will typically have a preferred specialty pharmacy network. You’ll need to fill your prescription within that network for coverage.

It’s possible that a specialty pharmacy will be selected for you. For example, your healthcare provider may refer you to specific pharmacies that will be able to give you the best price. That specialty pharmacy will handle your prescription from start to finish.

This includes:

• Getting the prescription from your healthcare provider

• Apply any available manufacturer copay savings cards

• Handling the billing and any financial assistance applications

• Taking care of any authorizations that are needed

• Filling the medication

• Training you on how to use it

The pharmacy may ship the medication to your home. But sometimes they might ship it to your healthcare provider’s office. Depending on what type of medication it is, you may not be able to administer it yourself.

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Written by:

Ashley Wong, PharmD

Ashley Wong, PharmD, is a licensed pharmacist in California. She has over 6 years of experience providing drug information.

Edited by:

Alyssa Billingsley, PharmD

Alyssa Billingsley, PharmD, is the director of pharmacy content for GoodRx. She has over a decade of experience as a pharmacist and has worked in clinical, academic, and administrative roles.

Reviewed by:

Christina Aungst, PharmD

Christina Aungst, PharmD, is a pharmacy editor for GoodRx. She began writing for GoodRx Health in 2019, transitioning from freelance writer to editor in 2021.

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