Key takeaways
- Repatha works by blocking a specific enzyme in your liver to help your body remove cholesterol more effectively. It is not an immunosuppressant drug, so it doesn’t work by suppressing the immune system.
- But Repatha can cause certain infections, such as the flu or common cold, as side effects.
Repatha is an injection doctors prescribe to lower the risk of heart attack or stroke and the need for particular heart surgeries in some adults. They also prescribe it to decrease low-density lipoprotein (LDL) cholesterol in some adults and children.
Repatha works by attaching to a specific enzyme in your liver. While it doesn’t suppress your immune system, side effects such as upper respiratory tract infections are possible with Repatha.
Read on to learn more about other side effects of Repatha and how the drug works.

Like most drugs, Repatha can cause side effects. Most of the side effects of Repatha are mild and easy to manage, but serious side effects are possible with the drug.
The more common side effects reported in studies of Repatha depended on the condition the drug aimed to treat. See the table below for a list of the drug’s more common side effects.
| Condition | More common side effects |
|---|---|
| lower cholesterol levels | • back pain • injection site reactions • upper respiratory tract infection, such as the flu or common cold |
| lower the risk of heart attack, stroke, and needing types of heart surgeries | • increased blood sugar level or diabetes • upper respiratory tract infection, such as the flu or common cold • runny nose or sore throat |
While Repatha doesn’t work by suppressing the immune system, people receiving Repatha for either condition reported certain types of infections as side effects. Urinary tract infections (UTIs), while not commonly reported, are also a side effect of Repatha.
Talk with your doctor or pharmacist if you have questions about your risk of some infections or other side effects while receiving Repatha.
Find answers to some commonly asked questions about Repatha.
Can Repatha cause cancer or autoimmune problems?
No. People didn’t report cancer and autoimmune problems as side effects in Repatha’s studies.
Some
Talk with your doctor or pharmacist if you have more questions about Repatha, cancer, or autoimmune problems.
How does Repatha work?
Repatha’s mechanism of action (how it works) is to attach to an enzyme called PCSK9 in your liver. (An enzyme is a protein that helps many reactions happen in the body). Repatha blocks this enzyme from working. This blocking helps your body remove cholesterol more effectively.
Lower cholesterol also helps lower your risk of complications of heart disease, such as heart attack or stroke.
If you have questions about how Repatha works, talk with your doctor or pharmacist.
Repatha is an injection doctors prescribe to treat high cholesterol and other heart-related conditions.
It works by blocking an enzyme in your liver, helping cholesterol move more efficiently from your body. Repatha doesn’t suppress your immune system but can cause specific infections as a side effect.
Talk with your doctor or pharmacist if you have questions about Repatha and your immune system.



