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

Porfimer sodium belongs to a group of cancer-fighting medications known as antineoplastics. It kills cancer cells by making them more sensitive to the destructive effects of a laser light, which is aimed at them after injecting the medication. This procedure is called photodynamic therapy.

Porfimer sodium is used to treat a certain type of bladder cancer, cancer of the esophagus (the tube that carries food from the throat to the stomach), endobronchial cancer (the tubes that go to the lungs), and Barrett's esophagus (a disorder of the lining of the esophagus).

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 receiving this medication, speak to your doctor.

What form(s) does this medication come in?

Each vial contains porfimer sodium 75 mg as a sterile freeze-dried cake or powder. Nonmedicinal ingredients: sodium hydroxide and/or hydrochloric acid to adjust pH. There are no antimicrobial preservatives or formulation excipients (nonmedicinal ingredients).

How should I use this medication?

The recommended dose of porfimer sodium is 2 mg per kilogram of body weight. It is injected into a vein through a specially prepared site on your skin. This is followed by treatment with laser light directed at the cancer about 40 to 50 hours later.

Bladder cancer is treated with only one course of treatment. Cancer of the esophagus, endobronchial cancer, and Barrett's esophagus may require a second treatment of laser light after a further 96 to 120 hours. Up to 2 more courses of medication and light therapy may be used if necessary to treat these cancers.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. Your doctor may choose a different schedule different from those listed here.

Very careful handling of this medication is required. Porfimer sodium should only be given by health care professionals familiar with the use of cancer chemotherapy. It is always given under the supervision of a doctor in a hospital or similar setting with access to sterile equipment for preparation.

As well as killing cancer cells, porfimer sodium and laser treatment 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 "What side effects are possible with this medication?" section.

It is important this medication be given exactly as recommended by your doctor. If you miss an appointment to receive porfirmer sodium, contact your doctor as soon as possible to reschedule your appointment.

This medication will be stored at the hospital where you receive treatment.

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 take porfimer sodium if you:

  • are allergic to porfimer sodium, porphyrins, or any ingredients of the medication
  • have a bladder tumour of stage greater than T1 and has invasive cancer
  • have a functional bladder capacity less than 200 mL
  • have a liver condition known as porphyria
  • have esophageal cancer along with tracheoesophageal or bronchoesophageal fistula
  • have esophageal or gastric varices or an esophageal ulcer more than 1 cm in diameter (for Barrett's esophagus)
  • have had prior total bladder irradiation
  • have severe acute respiratory distress caused by an obstructive endobronchial lesion
  • have tumours eroding into a major blood vessel

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.

  • anxiety
  • constipation
  • eye pain when looking into bright light
  • frequent urination
  • hair growth, discoloration of the skin, skin wrinkles and skin thinning, or fragile skin can occur (in areas that have had a reaction from the sun)
  • headache
  • hiccups
  • increased sensitivity of the skin to light (e.g., redness, swelling, itching, burning sensations of the skin)
  • increased urination at night
  • nausea
  • sleeping problems
  • unusual tiredness or weakness
  • vomiting

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

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

  • abdominal or stomach pain
  • abnormal or fast heartbeat
  • bloody or cloudy urine
  • chest tightness or wheezing
  • chills
  • coughing
  • difficult, burning, or painful urination
  • difficulty breathing
  • difficulty swallowing
  • fever
  • mouth sores
  • severe constipation
  • severe dizziness
  • severe nausea and vomiting
  • signs of anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
  • 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)
  • swelling of the face, feet, or lower legs
  • symptoms of a urinary tract infection (e.g. pain when urinating, urinating more often than usual, low back or flank pain)
  • unusual infections (symptoms may include fever or chills, sore throat, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, white patches inside the mouth, or listlessness)

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

  • chest pain
  • painful or difficult breathing
  • severe abdominal or stomach pain
  • shortness of breath
  • spitting or vomiting blood

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.

Breathing: This medication may cause shortness of breath and difficulty breathing in the time between receiving porfimer sodium and laser treatment. Contact your doctor immediately if these symptoms occur.

Chest pain: Some people may experience chest pain while receiving this medication as a result of how this medication works. Let your doctor know if this occurs.

Infection: As well as killing cancer cells, this medication can reduce the number of cells that fight infection in the body (white blood cells). If possible, avoid contact with people with contagious infections. Tell your doctor immediately if you begin to notice signs of an infection, such as fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness. Your doctor will do blood tests regularly to monitor the number of specific types of blood cells in your blood.

Sun sensitivity: Exposure of the eyes and skin to direct sunlight (or brightly focused indoor light) should be avoided for at least 30 days (and up to 90 days) after receiving porfimer sodium.

  • Do not expose your skin to direct sunlight or to bright indoor lights for at least 30 days after injection. People going outdoors within this timeframe should wear protective clothing and dark sunglasses. Check with your doctor about the best sunglasses to use to project your eyes. Regular sunscreens do not protect the skin and eyes from a reaction. Talk to your doctor about how to tell when it is all right to resume your normal routine with respect to sunlight and bright light exposure.
  • Do not stay in a darkened room during this period, as normal indoor light helps to break down the medication safely.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. Women who may become pregnant should use effective contraception while taking this medication. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: It is not known if porfimer sodium passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

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

What other drugs could interact with this medication?

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

  • acitretin
  • adapalene
  • amiodarone
  • celecoxib
  • amphoteracin B
  • corticosteroids (e.g., dexamethasone, methylprednisolone, prednisone)
  • dimethyl sulfoxide (DMSO)
  • fluoroquinolone antibiotics (e.g., ciprofloxacin, levofloxacin, ofloxacin)
  • fluphenazine
  • griseofulvin
  • hydrochlorothiazide
  • isotretinoin
  • mannitol
  • nalidixic acid
  • non-steroidal anti-inflammatory medications (NSAIDs; e.g., diclofenac, ibuprofen, naproxen)
  • other cancer medications
  • phenothiazines (e.g., chlorpromazine)
  • prochlorperazine
  • sulfonamide antibiotics (e.g., sulfamethoxazole, sulfisoxazole)
  • sulfonylurea diabetes medications (e.g., chlorpropamide, glyburide)
  • tetracyclines (e.g., doxycycline, minocycline, tetracycline)
  • thiazide diuretics (e.g., hydrochlorothiazide, indapamide)
  • tretinoin
  • vemurafenib

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.