How does this medication work? What will it do for me?

Melphalan belongs to the group of cancer-fighting medications known as antineoplastics, and specifically to the group of antineoplastics known as alkylating agents.

Melphalan prevents the growth of cancer cells by interfering with the genetic material DNA, which is necessary for reproduction of cells. It is used to treat multiple myeloma (a type of blood cancer), malignant melanoma (a type of skin cancer), and cancer of the ovary.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

What form(s) does this medication come in?

Injection

Each vial of sterile, white to cream-coloured, freeze-dried powder contains melphalan HCl equivalent to melphalan 50 mg and povidone 20 mg. Each vial of solvent-diluent provides 10 mL of buffer solution containing sodium citrate 0.20 g, ethanol 0.52 mL, propylene glycol 6 mL, and water for injection, q.s.

Tablets

Each white to off-white, round, biconvex, film-coated tablet, imprinted with "A" on one side and "GX EH3" on the other side, contains melphalan 2 mg. Nonmedicinal ingredients: colloidal silicon dioxide, crospovidone, hydroxypropyl methylcellulose, magnesium stearate, microcrystalline cellulose, polyethylene glycol 400, and titanium dioxide.

How should I use this medication?

Melphalan is available as tablets and in an injectable form. There are many different dosing schedules used for treatment with melphalan tablets and melphalan injectable. A common adult dose of melphalan tablets for multiple myeloma is 6 mg daily for up to 2 to 3 weeks. After this time, the medication is usually stopped for a period of up to 4 weeks, and blood tests are carried out. A dose of 2 mg daily is often started on a regular basis following the waiting period.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

Melphalan injection will be injected by your doctor or by someone under direct supervision of your doctor. The dose is based on body size. It is usually injected into a vein through a specially prepared site on the skin. It is sometimes administered by a technique known as perfusion.

It is important to take this medication exactly as prescribed by your doctor. Your doctor may want you to drink extra fluids while taking this medication so that kidney problems are prevented. This medication may cause nausea, vomiting, and loss of appetite, but it is important that you continue to use it. Do not stop taking it without talking with your doctor.

If you vomit shortly after taking a dose of melphalan, call your doctor for instructions on whether to skip that dose or to take another dose. If you miss a dose of melphalan, skip the missed dose and continue with your regular dosing schedule, and inform your doctor. Do not take a double dose to make up for a missed one.

As well as interfering with the genetic material DNA of cancer cells, melphalan can interfere with some of your normal cells. This can cause a number of side effects. Keep track of any side effects and report them to your doctor as suggested in the section, "What side effects are possible with this medication?"

Store this medication in a cool, dry place, and protect it from direct light.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Do not use this medication if you:

  • are allergic to melphalan or any ingredients of this medication
  • are allergic to chlorambucil
  • have a cancer that has shown a resistance to melphalan in the past
  • have a low count of neutrophils (a type of white blood cell)
  • have a low platelet count
  • have received similar chemotherapy medications or radiation treatments recently

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • hair loss
  • loss of appetite
  • loss of menses in women
  • nausea and vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

  • diarrhea
  • difficulty in swallowing
  • joint pain
  • progressive shortness of breath
  • redness and/or soreness in arm or leg
  • signs of bleeding (e.g., bloody nose, blood in urine or stools, coughing blood, cuts that don't stop bleeding, unusual bleeding or bruising, or black, tarry stools)
  • signs of decreased red blood cells (anemia; e.g., pale skin, fatigue, shortness of breath, rapid heartbeat)
  • signs of infection (e.g., cough, fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
  • signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
  • signs of urinary tract infection (e.g., frequent urge to urinate, bloody or cloudy urine, pain with urination)
  • skin rash or itching
  • sores in mouth or on lips
  • swelling of feet or lower legs

Stop taking the medication and seek immediate medical attention if any of the following occur:

  • fast or irregular heartbeat
  • symptoms of a serious allergic reaction such as hives; difficulty breathing; or swelling of the eyelids, throat, and mouth

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Anemia: Melphalan may cause low levels of red blood cells. If you experience symptoms of reduced red blood cell count (anemia) such as shortness of breath, feeling unusually tired, or pale skin, contact your doctor as soon as possible.

Blood clotting: This medication can reduce the number of platelet cells in the blood. Platelets help the blood to clot, and a shortage could make you bleed more easily. Tell your doctor of any signs that your blood is not clotting as quickly. Such symptoms may include black and tarry stools, blood in the urine, easy bruising, or cuts that won't stop bleeding.

Fertility: Sterility may occur with the use of melphalan.

Gout: This medication may cause high levels of uric acid in the blood, making gout more likely to occur.

Infection and vaccines: As well as killing cancer cells, this medication can reduce the number of cells that fight infection in the body (white blood cells). Avoid contact with people with contagious infections and tell your doctor if you begin to notice the signs of an infection such as fever or chills. Also tell your doctor if you have been vaccinated, or are planning to be vaccinated with a live vaccine.

Kidney problems: Kidney disease or reduced kidney function may cause this medication to build up in the body, increasing the risk of side effects. If you have kidney problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Lung problems: In rare cases, melphalan can cause lung problems (pulmonary fibrosis, permanent scarring of the lungs or interstitial pneumonitis, inflammation of the lungs) that, in some cases, can be fatal. If you experience any difficulty breathing, wheezing, fever, shortness of breath, cough, or coughing up of blood, accompanied by weakness and weight loss while taking melphalan, tell your doctor immediately.

Secondary cancer: When used for long periods of time, this medication can increase the risk of developing leukemia. If you have any concerns, talk to your doctor about the risks and benefits of using this medication.

Pregnancy: There is a possibility of birth defect if either the man or the woman is taking melphalan at the time of conception, or if it is taken during pregnancy. Effective birth control should be practiced while using this medication.

This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: This medication passes into breast milk. If you are a breast-feeding mother and are taking melphalan, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of this medication have not been established for children. 

What other drugs could interact with this medication?

There may be an interaction between melphalan and any of the following:

  • amphotericin B
  • azathioprine
  • BCG
  • clozapine
  • cyclosporine
  • denosumab
  • echinacea
  • leflunomide
  • nalidixic acid
  • natalizumab
  • pimecrolimus
  • other cancer medications
  • roflumilast
  • tacrolimus
  • tofactitinib
  • vaccines

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.