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Myalept Side Effects

Generic Name: metreleptin

Note: This document contains side effect information about metreleptin. Some of the dosage forms listed on this page may not apply to the brand name Myalept.

For the Consumer

Applies to metreleptin: subcutaneous powder for solution, subcutaneous solution

Along with its needed effects, metreleptin (the active ingredient contained in Myalept) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking metreleptin:

More common
  • Anxiety
  • blurred vision
  • body aches or pain
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • chills or fever
  • cold sweats
  • confusion
  • dizziness
  • fast heartbeat
  • headache
  • increased hunger
  • nausea
  • nervousness
  • shakiness
  • sore throat
  • unusual tiredness or weakness
Less common
  • Bloating
  • pains in the stomach, side, or abdomen, possibly radiating to the back
  • vomiting

Some side effects of metreleptin may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common
  • Back pain
  • diarrhea
  • ear drainage
  • earache or pain in the ear
  • muscle pain or stiffness
  • pain in the joints
  • weight loss

For Healthcare Professionals

Applies to metreleptin: subcutaneous powder for injection


The most frequently reported side effects were headache, hypoglycemia, decreased weight, and abdominal pain.[Ref]


Very common (10% or more): Hypoglycemia (13%), decreased weight (13%)[Ref]

Nervous system

Very common (10% or more): Headache (13%)
Common (1% to 10%): Dizziness, paresthesia[Ref]


Very common (10% or more): Abdominal pain (10%)
Common (1% to 10%): Nausea, diarrhea, pancreatitis[Ref]

It has been reported that two patients (4%) had symptoms of pancreatitis. Both had a medical history of pancreatitis.[Ref]


Frequency not reported: Autoimmune disorder, immunogenicity[Ref]

In vitro neutralizing activity anti-metreleptin antibodies were identified in 2 patients (n=33) with generalized lipodystrophy who showed severe infections and worsening metabolic control (increases in HbA1c and/or triglycerides). Three patients with anti-metreleptin antibodies without lipodystrophy showed excessive weight gain, and/or development of glucose intolerance or diabetes.

In clinical trials, anti-metreleptin antibodies were detected in 36 of 43 generalized lipodystrophy patients, with titers ranging from 1:5 to 1:1,953, 125; however, these numbers may be misleading as detection of antibody formation is highly dependent on the sensitivity and specificity of the assay (the assays utilized in clinical trials lacked sensitivity), handling of the sample, concomitant drugs, and underlying disease. Due to incompleteness of the immunogenicity data, the clinical significance and the magnitude and persistence of the anti-drug responses are not well characterized.[Ref]


Common (1% to 10%): Ovarian cyst


Common (1% to 10%): Anemia[Ref]


Common (1% to 10%): Injection-site erythema, urticaria
Frequency not reported: Generalized rash[Ref]


Common (1% to 10%): Arthralgia, back pain[Ref]


Common (1% to 10%): Pyrexia, ear infection, fatigue[Ref]


Common (1% to 10%): Proteinuria[Ref]


Common (1% to 10%): Upper respiratory tract infection[Ref]


Three cases of T-cell lymphoma were reported among patients with acquired generalized lipodystrophy; 2 patients diagnosed with peripheral T-cell lymphoma during treatment had immunodeficiency and significant hematologic abnormalities including severe bone marrow abnormalities prior to starting treatment. Anaplastic large cell lymphoma was reported in 1 patient receiving this drug who did not have hematologic abnormalities before treatment.

Frequency not reported: T-cell lymphoma, anaplastic large cell lymphoma


1. "Product Information. Myalept (metreleptin)." Bristol-Myers Squibb, Princeton, NJ.

Some side effects of Myalept may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.