Key takeaways:
Repatha (evolocumab) is an injectable PCSK9 inhibitor. It’s used to lower high cholesterol from different causes and to reduce the risk of heart attack and stroke in people with heart disease.
Common Repatha side effects include cold and flu symptoms, back pain, and injection site reactions. Urinary tract infections (UTIs) are also possible.
If any Repatha side effects become bothersome, get worse, or don’t improve over time, let your prescriber know. Seek immediate medical care if you develop symptoms that feel life-threatening, such as swelling of the face, tongue, or throat.
Save on related medications
If you have high cholesterol, there’s a newer medication class your healthcare team may consider: PCSK9 inhibitors. Usually, you’d be prescribed one of these medications after you’ve already tried a statin. You could also be prescribed a statin and a PCSK9 inhibitor together.
Repatha (evolocumab) is an injectable PCSK9 inhibitor that works well to lower high cholesterol from different causes. And if you have heart disease, it can help lower your risk of heart attack and stroke.
But like any medication, side effects are possible with Repatha. Cold and flu symptoms, back pain, and injection site reactions are a few examples.
Repatha side effects at a glance
Common Repatha side effects are often mild and can usually be managed at home. Rare but serious side effects may need medical attention.
Repatha can be administered at a lower dose that’s injected every 2 weeks or a higher dose that’s injected once a month. The likelihood of side effects appears to be higher with the once-monthly dosage.
Common side effects
The following side effects were reported by at least 3% of people who received Repatha in clinical trials:
Cold and flu symptoms
Injection site reactions
Urinary tract infections (UTIs)
Muscle pain
Diarrhea
Dizziness
Headaches
Serious side effects
While less common, Repatha can also cause these potentially serious side effects:
Hypersensitivity reactions, including angioedema and anaphylaxis
Higher blood glucose (sugar) levels
Below, we cover six notable Repatha side effects you may experience during treatment.
1. Cold and flu symptoms
Cold and flu symptoms are a common Repatha side effect. These symptoms can include cough, runny nose, and a sore throat. Sometimes, they’re from upper respiratory tract infections (URTIs), which are also reported by people using Repatha. Examples of URTIs include the common cold and sinus infections.
Cold and flu symptoms often resolve on their own. But if they’re bothersome, there are a few things you can do. You can use a saline nasal spray, drink plenty of fluids, and use a humidifier. You can also try over-the-counter (OTC) cold medications if they’re safe for you to take.
If you have a URTI that’s caused by a virus, you should start feeling better within a week. But if you have a bacteria-related URTI, which is less common, you may need antibiotics. Contact your healthcare team if your symptoms don’t go away or become severe.
2. Back pain
You may experience back pain as a Repatha side effect. Experts don’t know for sure why this happens. But there are a few things that can help if you develop back pain while using Repatha:
Exercising regularly in a way that’s safe and appropriate for you
Performing stretches that support lower back muscles
Using heat or ice packs
Adjusting your sleep position
Taking an OTC pain reliever, if appropriate
Talk to your healthcare team if you have bothersome back pain. Severe back pain that doesn’t go away could mean there’s something else going on. Your healthcare team can help determine the likely cause of your back pain and recommend next steps.
3. Injection site reactions
Like many injectable medications, Repatha can cause reactions where you inject it. These injection site reactions may include pain, redness, and swelling of the area after a dose.
To help lower the risk of injection site reactions:
Follow your healthcare team’s instructions for how to inject Repatha.
Rotate injection sites each time you inject a dose.
Allow Repatha to come to room temperature before injecting it.
Most injection site reactions go away on their own after a few hours or a few days. If your symptoms don’t get better, or get worse, talk to your healthcare team. They can recommend how to handle the reaction.
4. Higher blood sugar levels
Higher blood sugar levels is another reported Repatha side effect. During clinical trials, compared to people who weren’t given Repatha, a slightly higher percentage of people taking the medication for heart attack and stroke reduction developed diabetes. However, other studies haven’t found an increased risk.
If you’re already living with Type 2 diabetes and taking a statin, Repatha can provide additional cholesterol benefits. But if you find that your blood sugar levels are higher than usual after starting Repatha, let your prescriber know.
5. Urinary tract infections
Repatha may also be associated with a higher risk of UTIs. It’s not clear exactly why people taking Repatha might be more likely to get UTIs. Fortunately, there are effective UTI treatments available.
UTI symptoms can include pain or burning when urinating, cloudy or pink urine, and the need to pee frequently. Let your healthcare team know if you have these symptoms. If you have a UTI, they’ll likely recommend starting an antibiotic, which will take a few days to work. In the meantime, the OTC product AZO (phenazopyridine) can help ease UTI pain.
6. Hypersensitivity reactions
Repatha may cause hypersensitivity reactions, which can range from mild to severe. Mild reactions may include rash, eczema, or itching. More serious reactions, such as swelling under the skin (angioedema) or anaphylaxis, are also possible.
You may not know if you’re allergic to evolocumab, Repatha’s active ingredient, before starting treatment. But if you have a known allergy to any of the inactive ingredients in Repatha, you should avoid using it.
Also, note that the needle cover on some Repatha pens contains a form of latex, which may cause a reaction in people with latex allergies. Make sure your pharmacist and prescriber know if you have a latex allergy, so they can ensure you use a latex-free pen.
Anaphylaxis can be life-threatening. Symptoms can include widespread skin reactions, throat swelling, trouble breathing, and dizziness. Seek emergency medical care right away if these or any symptoms that feel life-threatening occur.
If you have a mild allergic reaction to Repatha after starting treatment, contact your healthcare team. They may recommend ways to manage your symptoms or switch you to a different medication.
Frequently asked questions
Weight gain wasn’t reported as a side effect of Repatha during clinical trials. However, Repatha has been associated with higher blood sugar levels, which may contribute to weight changes in some people over time. Other factors, such as diet, activity level, or underlying health conditions, may also affect body weight.
If you notice unexpected weight gain while using Repatha, talk to your healthcare team. They can help determine the possible cause and recommend next steps.
Repatha is injected under the skin using an autoinjector pen. Possible injection sites include the stomach, upper thigh, and upper arm. Your healthcare team can show you how to inject it safely at home.
To inject Repatha using the SureClick autoinjector pen:
Remove the orange cap from the pen.
Pinch a 2-inch area of skin at the injection site.
Place the pen at a 90-degree angle against your skin, firmly pushing it down until the yellow safety guard stops moving. Keep holding it down.
Press the gray button. You may hear a click.
Keep holding the pen against your skin until the window turns completely yellow. (This may take up to 15 seconds.) You may hear another click.
Remove the pen from your skin and throw it away in a sharps container.
Repatha can be kept at room temperature (up to 77°F) in its original carton for up to 30 days. Once it reaches room temperature, you shouldn’t put it back in the refrigerator. If you leave a Repatha pen out longer than 30 days, you should throw it away.
Weight gain wasn’t reported as a side effect of Repatha during clinical trials. However, Repatha has been associated with higher blood sugar levels, which may contribute to weight changes in some people over time. Other factors, such as diet, activity level, or underlying health conditions, may also affect body weight.
If you notice unexpected weight gain while using Repatha, talk to your healthcare team. They can help determine the possible cause and recommend next steps.
Repatha is injected under the skin using an autoinjector pen. Possible injection sites include the stomach, upper thigh, and upper arm. Your healthcare team can show you how to inject it safely at home.
To inject Repatha using the SureClick autoinjector pen:
Remove the orange cap from the pen.
Pinch a 2-inch area of skin at the injection site.
Place the pen at a 90-degree angle against your skin, firmly pushing it down until the yellow safety guard stops moving. Keep holding it down.
Press the gray button. You may hear a click.
Keep holding the pen against your skin until the window turns completely yellow. (This may take up to 15 seconds.) You may hear another click.
Remove the pen from your skin and throw it away in a sharps container.
Repatha can be kept at room temperature (up to 77°F) in its original carton for up to 30 days. Once it reaches room temperature, you shouldn’t put it back in the refrigerator. If you leave a Repatha pen out longer than 30 days, you should throw it away.
The bottom line
Common Repatha (evolocumab) side effects include cold and flu symptoms, back pain, and injection site reactions. Urinary tract infections (UTIs) are also possible. While rare, severe allergic reactions, including anaphylaxis, have been reported with Repatha.
If you’re unsure about using Repatha because of the possible side effects, talk to your healthcare team. They can help you know what potential side effects to expect.
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References
Amgen USA. (2026). Repatha - evolocumab injection, solution, Repatha - evolocumab kit [package insert]. DailyMed.
Memon, R. J., et al. (2023). Angioedema. StatPearls.
Rosenson, R. S., et al. (2019). Efficacy and safety of evolocumab in individuals with Type 2 diabetes mellitus: Primary results of the randomised controlled BANTING study. Diabetologia.
Sabatine, M. S., et al. (2017). Evolocumab and clinical outcomes in patients with cardiovascular disease. The New England Journal of Medicine.
