Defalix

Indications

Difelikefalin is used to treat moderate to severe itching (pruritus) in adults with chronic kidney disease who are on haemodialysis. This kind of itching is common in people with kidney failure and can disturb sleep and quality of life.

How It Works

Difelikefalin activates kappa opioid receptors, mainly on nerve endings and immune cells outside the brain. This calms the nerve signals that cause itching and reduces inflammation in the skin. Because it does not easily enter the brain, it has a lower risk of the effects seen with typical opioid painkillers, such as addiction or slowed breathing.

Dosage and Administration

Difelikefalin is given as an injection into the dialysis line (into a vein) by a nurse or doctor at the end of each haemodialysis session, usually three times a week. The dose is based on your target dry body weight and is always as prescribed. If a dialysis session is missed, the dose is given at the next session. It is not taken at home.

Interactions

• Medicines that cause drowsiness or dizziness, such as sedating antihistamines, sleeping pills, Gabapentin, Pregabalin and opioid painkillers, may add to sleepiness and dizziness.
• Alcohol can increase drowsiness.

Tell your dialysis team about all medicines you take.

Contraindications

• Allergy to Difelikefalin or any ingredient of the injection.

Side Effects

Common side effects include diarrhoea, dizziness, drowsiness or sleepiness, nausea, headache, tingling (pins and needles) and changes in mental state such as confusion. Unsteadiness may increase the risk of falls, especially in older people. Raised potassium levels have been reported.

Get urgent medical help if you have severe drowsiness, confusion, fainting, a fall with injury, or signs of an allergic reaction such as swelling of the face or throat, difficulty breathing or a widespread rash.

Pregnancy and Lactation

There is little information on use in pregnancy, so it is usually avoided unless the doctor decides the benefit outweighs the risk. It is not known whether it passes into breast milk; discuss breastfeeding with your doctor.

Precautions and Warnings

• Given only by health professionals during dialysis.
• It may cause dizziness and sleepiness; do not drive or use machines until you know how it affects you, especially after dialysis.
• Take care to avoid falls; tell the team if you feel unsteady.
• Not studied in people on peritoneal dialysis or with severe liver disease.
• Report any increase in itching or new skin problems.

Overdose

An overdose is unlikely as it is given by health professionals. Too much may cause marked drowsiness, dizziness and confusion. Treatment is supportive; extra dialysis may help remove it.

Therapeutic Class

Antipruritic agent; peripherally acting kappa opioid receptor agonist.

Storage

Hospital item: store as directed on the pack, usually below 25°C, protected from light. Do not freeze.