Metreleptin (Subcutaneous)

Metreleptin is a synthetic hormone used to replace the body's natural leptin most commonly in patients diagnosed with generalized lipodystrophy.


Metreleptin, sold under the name of Myalept, is a synthetic hormone given to patients with dyslipidemia and severe diabetes. It is only available on prescription, from medical institutions and healthcare professionals which are specifically enrolled in this treatment program and that have signed up to the relevant risk and evaluation strategy for this medication.

It has been approved for used in Japan, to treat patients suffering from certain types of metabolic disorder. In the United States, the drug has been approved to use in replacement therapies for patients who have been diagnosed with a leptin deficiency as a complication of lipodystrophy.

Metreleptin is often combined with a specially-planned and strictly enforced diet for patients suffering from generalized lipodystrophy.

This rare condition is a disease which affects the metabolism is dramatic and dangerous ways. The result is that patients have little or no fat cells in their body, affecting the patient's appearance and energy levels as well as resulting in a potentially dangerous hormonal imbalance. Metreleptin works to artificially redress this imbalance by acting as a substitute for leptin within the body.

Leptin is a key ingredient in many of the body's metabolic processes. It is responsible for stopping you from feeling hungry once you have eaten and works in conjunction with ghrelin to balance energy levels.

Metreleptin is a form of medication which is injected by the patient once a day. It is supplied in the form of a powder, and it requires mixing with liquid before it can be safely used by patients. The liquid will can vary according to the patient's needs but will be prescribed along with the Metreleptin powder.

Patients will need to be shown how to inject the medication safely before they are able to take the prescription home. The medication should be taken once a day, and if possible, it should be injected at the same time every day. Patients can choose a time which suits them, preferably before they start taking the treatment, and stick to this as much as possible. Patients are also able to choose an injection site which suits them. This is usually in the upper arm abdomen or thigh.

Initial doses are calculated based on the age, weight, gender and condition of the patient. The dose may then be adjusted or increase according to how the patient responds to the medication over time.

Conditions treated

  • Leptin deficiency
  • generalized lipodystrophy

Type of medicine

  • Synthetic hormone

Side Effects

Although Metreleptin has been developed to replicate a naturally occurring substance within the body, it still comes with the risk of side effects. Doctors will be aware of the risk of side effects associated with this medication and will make a decision in each patient's case to weigh up whether the potential benefit to the patient's health is greater than the possible risk of harmful side effects. If the doctor goes ahead and prescribes the drug, they will be doing so on the belief that this is what is best for the patient.

Most patients using Metreleptin will only experience mild side effects, if any at all. The most common of these side effects are:

  • Headaches
  • Low blood sugar levels
  • Abdominal cramps
  • Stomach pain
  • Weight loss

The symptoms listed above are common and are not usually indicators of any complications with the drug. Patients only need to seek medical attention if the symptoms are particularly severe or long-lasting. If this is the case, doctors may be able to help you manage the side effects, adjust the dose of Metreleptin or prescribe another form of treatment specifically aimed at minimizing the side effects.

Low blood sugar is a common side effect of Metreleptin, and this condition can produce its own symptoms as a result. Symptoms to look out for as a sign of low blood sugar levels include:

  • Headaches
  • Confusion
  • Dizziness
  • Lightheadedness
  • Weakness
  • Shakiness and unsteadiness
  • Irritability
  • Hunger
  • Feeling anxious or jittery
  • Sweating
  • Increased heartbeat

Patients can speak to their doctors about the best way to prevent and manage low blood sugar levels.

In addition to those listed above, taking Metreleptin can, in a small number of cases, lead to more severe side effects. These side effects include:

  • Loss of efficiency of the drug over time
  • Lowering of levels of natural leptin within the body
  • Serious infections
  • Difficult regulating blood sugar levels
  • Increased levels of fat in the blood
  • Worsening of autoimmune symptoms
  • Lymphoma

Some of the side effects listed above are secondary conditions which are hard to detect. It is extremely important for patients receiving Metreleptin treatment to attend all of their appointments with doctors and hospitals so that tests can be run to check for some of the side effects which are more difficult to spot through symptoms. If patients do suspect that they have developed any of the symptoms or conditions listed above, they should seek urgent medical attention and ensure that the doctor is aware that they have been using Metreleptin.

Allergic reactions to Metreleptin are rare but possible. Contact your doctor immediately if you experience any of the following symptoms whilst taking Metreleptin:

  • Rash
  • Hives
  • Swelling at the injection site, or of the face, tongue or throat
  • Itching
  • Difficult breathing
  • Dizziness and/or fainting

Patients experiencing any or all of the symptoms listed above could be experiencing an allergic reaction, and possibly a reaction to Metreleptin. These patients should seek urgent medical attention and make sure that the healthcare professionals treating them are aware that they have been taking Metreleptin injections.


Patients should not stop or start taking Metreleptin, or change their dosage, without consulting a doctor.

Metreleptin comes in the form of a powder which must be mixed with a medical liquid, prescribed alongside the Metreleptin.

Dosages will be set by the doctor and will vary depending on the patient's age, weight, general medical condition and gender.

It is possible for newborn babies and small infants to be prescribed Metreleptin, however, they will be prescribed a different fluid for the powder to be mixed with. The liquid for newborns and babies will be a sterile water which contains no preservatives, and this must be injected immediately following preparation.

For older children and adults, the active Metreleptin powder is combined with bacteriostatic water. As this liquid includes a preservative, doses which have been mixed up can be stored and used for up to 3 days as long as they remain refrigerated.


Whenever two or more pharmaceutical products are used at the same time there is always a risk of interaction between them. Interactions between drugs can cause one or more of the drugs to stop working as effectively, can aggravate underlying health conditions and can increase the risk or severity of any side effects. In order to minimize the risk of interactions between drugs patients should make sure that they keep an accurate and up-to-date record o all of the drugs that they are currently taking or have recently stopped taking. This list should include any non-prescription and over-the-counter medication as well as all dietary supplements, vitamin tablets and any illegal substances which are taken. This will give doctors the best chance of being able to avoid any interactions between drugs.

No formal studies have been conducted into the particular

However, as interactions between medications can increase the severity of any side effects, patients should take particular care to make sure that their doctor is aware of any medication they are taking carries a risk of the following side effects:

  • Headaches
  • Low blood sugar levels
  • Abdominal cramps
  • Stomach pain
  • Weight loss
  • Loss of efficiency of the drug over time
  • Lowering of levels of natural leptin within the body
  • Serious infections
  • Difficult regulating blood sugar levels
  • Increased levels of fat in the blood
  • Worsening of autoimmune symptoms
  • Lymphoma

Interactions can also occur between drugs and pre-exiting medical conditions. Patients taking Metreleptin can experience a worsening in their condition if they suffer from any of the following:

  • Autoimmune disorders
  • Diabetes


As with any form of medication, there are risks associated with using Metreleptin. Patients with certain conditions may find that other parts of their health are affected when they begin taking Metreleptin. As long as doctors have all of the information up front, they will be able to weigh up the possible outcomes and make an informed decision about your treatment. It is especially important for patients to inform their healthcare provide if any of the following statements are true:

  • You have had problems with your blood cell counts, particularly a low white blood cell count
  • You have ever experienced conditions affecting your bone marrow
  • You use insulin, or have previously used insulin
  • You are pregnant, or plan on becoming pregnant whilst receiving this treatment
  • You are breastfeeding, or plan on breastfeeding whilst taking this medication
  • You have ever suffered from illnesses affecting your pancreas
  • You are currently using, or have ever used, a sulfonylurea
  • You have ever suffered from an autoimmune disease
  • You have ever suffered from swollen lymph nodes
  • You have ever been diagnosed with a lymphoma
  • You have been told that you have high blood triglyceride levels

It is not known whether Metreleptin can harm an unborn baby, or whether it passes into breast milk if taken by a breastfeeding mother. If you are pregnant, plan on becoming pregnant or you are breastfeeding or planning to breastfeed, you should speak to your doctor about the possible implications of taking Metreleptin at the same time.

Patients should be careful not to inject this medication into the muscle or straight into a vein.

Occasionally, doses of Metreleptin can become discolored or develop lumps within the vials of medication, or for particles or sediment to appear. Any medication which has undergone on any of these changes should not be used at all.

Patients should never start taking, stop taking or change their dose of Metreleptin without first speaking to their doctor.

Metreleptin is prescribed along with a specific diet plan for patients with generalized lipodystrophy. The Metreleptin can stop being effective if this diet is not followed.

For patients also using insulin

Many patients who are prescribed Metreleptin will also be taking insulin injections. Both of these drugs can be used together and can be injected at the same time in order to make life easier for the patient. However, it is very important to use separate syringes and vials for the insulin and the Metreleptin. Follow the separate instructions for taking each drug and do not inject them both into the same site. The daily dose of insulin may have to be adjusted after patients start taking Metreleptin as the drug can cause low blood sugar.


Metreleptin should be refrigerated at a temperature of between 2°C and 8°C (36°F and 46°F).

As with all medication, Metreleptin should be stored within its original packaging. The vials should be kept in their outer cardboard cartons in order to protect the medication inside from exposure to direct sunlight. The medication should always be clearly labelled and remain out of reach of children and pets. Needles and syringes are to be stored separately to the medication.

Metreleptin should never be frozen. Under no circumstances should patients use Metreleptin which is out of date, frozen, discolored or has visible lumps inside.

Any unused or out-of-date medication needs to be disposed of safely and responsibly. Patients can return unwanted medication to their doctor or pharmacist as part of a medicine take-back program. Metreleptin should not be flushed down the toilet or disposed of with normal household waste.

It is possible to keep doses of Metreleptin refrigerated for up to 3 days once opened. Any Metreleptin which has been open for more than 3 days should be disposed of in a safe manner and not used.


Metreleptin, also distributed under the trade name of Myalept, is an artificial hormone which is prescribed to patients with lipodystrophy. It is a powerful new medication, developed in order to redress the imbalance of hormones suffered by people with this condition. As it is such a powerful medication, Metreleptin is only available on prescription. It is a controlled substance which is only issued by healthcare professionals working in medical institutions a are specifically enrolled in this treatment program.

Metreleptin is prescribed in conjunction with a specially-designed diet which is crucial to its success. The diet ensures that patients are able to continue eating at a rate which can be processed given the changes to their metabolism following prescription of the drug.

Lipodystrophy is a rare disease affecting the metabolism is dramatic and harmful ways. This results in patients have little or no fat cells in their body and a potentially dangerous hormonal imbalance. Metreleptin acts as a substitute for leptin, so that the balance of hormones is restored, and the metabolism can begin to function at a more normal rate.

The medication is injected once a day, potentially for the rest of a patient's life. Patients are shown how to inject this medication themselves so that they can take control of their own treatment and be able to live independent lives. The medication must be kept in the refrigerator and patients must be careful to ensure that they attend all appointments and checkups with their doctors and healthcare professionals. Metreleptin has not been known to cause serious side effects for most patients, however there is a risk of patients using this medication developing serious and sometimes difficult-to-detect conditions as a result. It is therefore vital that certain tests are performed on a regular basis in order to monitor each patient's condition and progress.