Streptozotocin is a chemotherapy drug that is given as a treatment for a rare type of cancer called a carcinoid tumour (neuroendocrine tumour). It is currently not licensed in the UK and is only available to a small number of people whose specialists think that it may help them. This is known as named-patient prescribing.
This information describes streptozotocin, how it is given and some of its possible side effects.

What streptozocin looks like

Streptozocin is a colourless fluid.

How it is given

Streptozocin may be given:

• As a drip (infusion) through a fine tube (cannula) inserted into the vein.
• It may also be given through a central line (Hicman or Portacath), which is inserted under the skin into a vein near the collarbone, or into a PICC line, which is inserted into a vein in the crook of the arm.
• Chemotherapy is usually given as a course of several sessions (or cycles) of treatment over a few months. The length of your treatment and the number of cycles you have will depend on the type of cancer for which you are being treated. Your nurse or doctor will discuss your treatment plan with you.

Possible side effects

Each person’s reaction to chemotherapy is different. Some people have very few side effects, while others may experience more. The side effects described in this information will not affect everyone who is given streptozotocin and may be different if you are having more than one chemotherapy drug.

We have outlined the most common side effects as well as rarer ones, so that you can be aware of them if they occur. However, we have not included those that are very rare and therefore extremely unlikely to affect you. If you notice any effects which you think may be due to the drug, but which are not listed in this information, please discuss them with your doctor or chemotherapy nurse.

Feeling sick (nausea) and being sick (vomiting)

If you do feel sick this may begin a few hours after the treatment is given and last for a few days. Your doctor can prescribe very effective anti-sickness (anti-emetic) drugs to prevent, or greatly reduce, nausea. If the sickness is not controlled, or continues, tell your doctor; they can prescribe other anti-sickness drugs which may be more effective. Some anti-sickness drugs can cause constipation. Let your doctor or nurse know if this is a problem.

Hair loss

This usually starts 3–4 weeks after the first dose of streptozocin, although it may happen earlier. Your hair may fall out completely, or may just thin. You may also have thinning and loss of eyelashes, eyebrows and other body hair. Hair loss is temporary and your hair will regrow once the treatment is finished.

Your liver may be affected temporarily

Streptozotocin may cause changes in the way that your liver works, though your liver will return to normal when the treatment is finished. This is very unlikely to cause you any harm, but your doctor will monitor this carefully. Samples of your blood will be taken from time to time to check your liver is working properly.

Your kidneys may be affected

Usually this does not cause any symptoms and the effect is usually mild, but if the effect is severe the kidneys can be permanently damaged unless treatment is stopped. For this reason your kidneys will be checked by a blood test before each treatment.

Less common side effects

Lowered resistance to infection

Streptozotocin can reduce the production of white blood cells by the bone marrow, making you more prone to infection. This effect can begin seven days after treatment has been given, and your resistance to infection usually reaches its lowest point 10–14 days after chemotherapy. Your blood cells will then increase steadily and will usually have returned to normal levels before your next cycle of chemotherapy is due.

Contact your doctor or the hospital straightaway if:

• your temperature goes above 38ºC (100.5ºF)
• you suddenly feel unwell (even with a normal temperature).

You will have a blood test before having more chemotherapy to make sure that your cells have recovered. Occasionally it may be necessary to delay your treatment if the number of blood cells (the blood count) is still low.

Bruising or bleeding

Streptozotocin can reduce the production of platelets (which help the blood to clot). Let your doctor know if you have any unexplained bruising or bleeding, such as nosebleeds, blood spots or rashes on the skin, and bleeding gums. Your platelet count will be checked before each treatment.

Anaemia (low number of red blood cells)

While having treatment with streptozocin you may become anaemic. This may make you feel pale, tired, and short of breath on exertion. Let your doctor or nurse know if these symptoms are a problem.

Sore mouth and ulcers

Your mouth may become sore, or you may notice small ulcers during this treatment. Drinking plenty of fluids, and cleaning your teeth regularly and gently with a soft toothbrush, can help to reduce the risk of this happening. Tell your nurse or doctor if you have any of these problems, as special mouthwashes and medicines to prevent or clear any mouth infection can be prescribed.

Taste changes

You may notice that your food tastes different. Normal taste will usually come back after the treatment finishes.

Tiredness and feeling weak

You may feel very tired. It is important to allow yourself plenty of time to rest.

Diarrhoea

This can usually be easily controlled with medicines such as imodium (loperamide) or codeine, but let your doctor know if it is severe or if it continues. It is important to drink plenty of fluids if you have diarrhoea.

The levels of sugar in your blood may change

Your blood-sugar levels will be checked by regular blood tests and you may be taught how to test your own levels at home. Some signs of a raised blood-sugar level are feelings of thirst, needing to pass urine more often and an increased appetite. Some signs of a low blood-sugar level are dizziness, confusion and sweating. Tell your doctor or nurse if you notice any of these.

Additional information

Leakage into the tissue

If streptozotocin leaks into the tissue around the vein it can damage the tissue in that area. If you notice any stinging or burning around the vein while the drug is being given, or any leakage of fluid from the cannula site, it is very important that you tell the doctor or nurse immediately.

If the area around the injection site becomes red or swollen at any time you should either tell the doctor or nurse on the ward, or if you are at home, ring the clinic or ward and ask to speak to the doctor or nurse.

Risk of blood clots

Cancer can increase your risk of developing a blood clot (thrombosis), and having chemotherapy may increase this risk further. A blood clot may cause symptoms such as pain, redness and swelling in a leg, or breathlessness and chest pain. Blood clots can be very serious so it is important to tell your doctor straightaway if you have any of these symptoms. However, most clots can usually be successfully treated with drugs to thin the blood. Your doctor or nurse can give you more information.

Other medicines

Some medicines can be harmful when you are having chemotherapy. Let your doctor know about any medications you are taking, including non-prescribed drugs such as complementary therapies and herbal drugs.

Fertility

Your ability to become pregnant or father a child may be affected by taking this drug. It is important to discuss fertility with your doctor before starting treatment.

Contraception

It is not advisable to become pregnant or father a child while taking streptozotocin, as the developing foetus may be harmed. It is necessary to use effective contraception while taking this drug and for at least a few months afterwards. Again, discuss this with your doctor.

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Further Information For Healthcare Professionals

ADVERSE REACTIONS SIGNIFICANT

>10%:

• Gastrointestinal: Nausea and vomiting (100%)
• Hepatic: Increased LFTs
• Miscellaneous: Hypoalbuminemia
• Renal: BUN increased, Clcr decreased, hypophosphatemia, nephrotoxicity (25% to 75%), proteinuria, renal dysfunction (65%), renal tubular acidosis

1% to 10%:

• Endocrine & metabolic: Hypoglycemia (6%)
• Gastrointestinal: Diarrhea (10%)
• Local: Pain at injection site

<1%:

• Confusion, lethargy, depression, leukopenia, thrombocytopenia, liver dysfunction, secondary malignancy
• Myelosuppressive:
  • WBC: Mild
  • Platelets: Mild
  • Onset: 7 days, Nadir: 14 days, Recovery: 21 days

MECHANISM OF ACTION

Interferes with the normal function of DNA by alkylation and cross-linking the strands of DNA, and by possible protein modification

PHARMACODYNAMICS / KINETICS

• Duration: Disappears from serum in 4 hours
• Distribution: Concentrates in liver, intestine, pancreas, and kidney
• Metabolism: Rapidly hepatic
• Half-life elimination: 35-40 minutes
• Excretion: Urine (60% to 70% as metabolites); exhaled gases (5%); faeces (1%)