Crohn’s disease (CD) is an inflammatory bowel disease that can affect any part of the gastrointestinal tract, but most often affects the end of the small intestine (ileum), the colon, or both. It’s not curable but you can work toward disease remission with effective treatment.

If your Crohn’s treatment is not working as well as you’d hoped, your doctor may recommend trying biologics. These are drugs made from living cells that target the inflammation response. They are most often used for moderate to severe Crohn’s that isn’t responding well to conventional therapies.

Like most medications, biologics have benefits and risks. They can reduce your inflammation, and in doing so, stall the progression of your Crohn’s. However, they can also put you at risk for infections and certain cancers.

Some doctors recommend avoiding the risks associated with biologics by saving that treatment for when other therapies aren’t working. Other doctors advocate for a “top-down” approach in which you try biologics sooner rather than later to stop intestinal damage before it starts.

Your doctor will help you weigh the risks and benefits so you can make an informed decision about whether to start treatment with biologics. Knowing about what to expect can make switching to biologics easier.

Your biologic must be taken via injection or intravenously because your stomach acids will destroy the delicate complexity of this drug.

Biologics are injected subcutaneously. This means the medication is deposited in the layer of fat between your skin and your muscle where it will slowly be absorbed. You can receive training to do your own injections or have them done by a medical professional.

Intravenous doses are given by infusion in a clinical setting. This method can take several hours. Wear comfortable clothing, bring snacks and entertainment, such as a book, and arrange to have a ride home afterward.

You may experience pain at the injection site, or changes such as:

  • itching
  • redness
  • bruising
  • swelling
  • pain
  • fever
  • chills
  • hives
  • headache

Biologics come with risks. These include:

  • Infection. Your
    ability to fight infection is reduced.
  • Cancer. There is
    a small increase in your likelihood of developing lymphoma.
  • Liver
    function changes.
    Your liver may be adversely impacted; notify
    your doctor immediately if you become jaundiced.
  • Arthritis. You may
    develop joint pain.
  • Lupus-like
    reaction (LLR).
    You may experience rash, fever, muscle ache, and
    joint pain.

Depending on your case, the possible benefits of biologic medicine may outweigh these risks. Your doctor can tell you more about the risks and help you make an informed decision about whether to take them.

If you stop taking biologics, they may not work as well when you start taking them again. This is because your body can build up antibodies that make the drug less effective. This is one of the reasons that doctors recommend continued use of biologics even if your Crohn’s is in remission. Another reason is that biologics are effective at maintaining remission by protecting you from reacting to flare triggers.

There are certain situations where your doctor will recommend taking a medication break, such as before surgery. For the most part though, expect your doctor to recommend consistent use of biologics.

Live vaccinations such as measles, mumps, rubella (MMR) are not recommended once you start biologics because of the risk of infection that this medication presents.

Biologics are relatively new. Because of this, the long-term effects on infants exposed to biologics during pregnancy aren’t known. Experts believe that the risk is low and conclude that the chance of fetal malformations while using biologics during pregnancy is close to that of the general population.

You and your doctor will need to discuss the risks of going off biologics during pregnancy versus the potential risk to your baby. It may be appropriate to take a medication break partway through your pregnancy depending on the type of biologic you are using. Babies exposed in utero to certain biologic medication may need to avoid being immunized with live attenuated vaccines until they are at least six months of age. Even then, they should be watched closely for signs of infection.

Biologics work by targeting and suppressing the inflammation response that can trigger Crohn’s flares. However, these medications come with side effects including reduced ability to fight infection. They require a subcutaneous injection or intravenous infusion.

You should continue taking your biologic even while in remission, unless instructed otherwise by your doctor.