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Generic name: difelikefalin
Dosage form: intravenous (bolus) injection
Drug class: Peripheral opioid receptor agonists

Medically reviewed by Philip Thornton, DipPharm. Last updated on Apr 4, 2023.

What is Korsuva?

Korsuva is a synthetic peptide and opioid agonist that is injected to treat pruritus or itchy skin in adults with chronic kidney disease (CKD) who are undergoing hemodialysis.

Korsuva was the first therapy to be approved by the US Food and Drug Administration (FDA) for this condition when it was approved in August 2021.

Korsuva works by targeting and activating the kappa opioid receptors in your peripheral nervous system. It's not known exactly how this helps to treat pruritus, but it's thought an imbalance in mu- and kappa-opioid receptor system activity plays a role in the development of pruritus.

What is Korsuva used for?

Korsuva is a prescription medicine used to treat moderate-to-severe pruritus associated with CKD in adults undergoing hemodialysis.

Korsuva is not recommended in patients undergoing peritoneal dialysis (fluid taken from abdomen).

Important information

Korsuva may cause serious side effects, including:

  • Dizziness
  • Sleepiness. Sleepiness is more likely to occur in patients who are 65 years or older.
  • Mental status changes, such as confusing
  • Trouble walking (which may lead to falls).

Taking Korsuva with centrally acting depressant medications (including anti-depressants and medicines used for anxiety, epilepsy, insomnia), sedating antihistamines (allergy medicines that can cause drowsiness), and opioid analgesics (certain pain medications) may increase the likelihood of these side effects.

Who should not receive Korsuva?

Do not take Korsuva is your are allergic to difelikefalin or any of the other ingredients in Korsuva. See below for a complete list of ingredients.

What should I tell my doctor before receiving Korsuva?

Before receiving Korsuva tell you doctor about all of your medical conditions including if you:

  • have depression, anxiety, epilepsy or insomnia and take a centrally acting depressant medication
  • have allergies and take a sedating antihistamine
  • have a condition that causes pain that you treat with an opioid analgesic

How should I receive Korsuva?

  • Korsuva is administered by a healthcare professional at the end of each hemodialysis treatment.
  • Korsuva is given by intravenous (IV) bolus injection through the venous line on your dialysis circuit.

What happens if I miss a dose?

If you miss a hemodialysis session and your dose of Korsuva, resume treatment with Korsuva again at your next hemodialysis treatment.

What should I avoid while receiving Korsuva?

Korsuva may impair your mental or physical abilities. You should not drive or operate dangerous machinery until the effect of Korsuva on your ability to drive or operate machinery is known.

Dosing information

The recommended dose of Korsuva is 0.5 mcg/kg given by intravenous bolus injection into the venous line of the dialysis circuit at the end of each hemodialysis treatment.

See the full prescribing information for further information about Korsuva dosing.

What are the side effects of Korsuva?

The most common side effects of Korsuva include:

  • diarrhea
  • dizziness
  • nausea
  • trouble walking (including falls)
  • high potassium
  • headache
  • sleepiness
  • mental status changes, such as confusion

These are not all of the possible side effects of Korsuva. Tell your doctor if you have any side effect that bothers you or does not go away.

You may report side effects to Vifor (International) Inc. at 1-844-835-8277 or FDA at 1-800-FDA-1088 or


Tell your doctor about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Pregnancy and breastfeeding

Tell your doctor if you are pregnant or plan to become pregnant. It is not known whether Korsuva will harm your unborn baby.

Tell your doctor if you are breastfeeding or plan to breastfeed. It is not known whether Korsuva passes into breast milk. Talk to your doctor about the best way to feed your baby if you receive Korsuva.


  • Store Korsuva vials at 20°C to 25°C (68°F to 77°F), excursions permitted to 15°C to 30°C (59°F to 86°F).
  • Do not freeze.
  • Prepared syringes of Korsuva can be stored at ambient temperature 20°C to 25°C (68°F to 77°F) until dosing. They must be administered within 60 minutes of syringe preparation.

What are the ingredients in Korsuva?

Active ingredients: difelikefalin acetate

Inactive ingredients: sodium chloride, acetic acid, sodium acetate, water

Korsuva is manufactured by Cara Therapeutics, Inc. Stamford, CT 06902 and marketed by Vifor (International) Inc., Rechenstrasse 37, 9014 St. Gallen, Switzerland.

Popular FAQ

Korsuva is thought to exert an anti-itching effect in hemodialysis patients by activation of kappa opioid receptors (KORs) on peripheral neurons and immune cells. Itching in patients undergoing hemodialysis is thought to be due to a build-up of toxins and an opioid system imbalance, including antagonism of peripheral KORs. Continue reading

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.