Pemetrexed
Indications
Pemetrexed is a cancer medicine used to treat non-squamous non-small cell lung cancer, either alone or with other medicines such as Cisplatin, Carboplatin or immunotherapy, and to treat malignant pleural mesothelioma (a cancer of the lining of the lungs).
How It Works
Pemetrexed is an antifolate chemotherapy. Cancer cells need folate (a B vitamin) to make DNA and divide. Pemetrexed blocks several enzymes that use folate, so the cancer cells cannot copy themselves and they die.
Dosage and Administration
Pemetrexed is given as an infusion into a vein by a doctor or nurse in hospital, usually once every 3 weeks. The dose is worked out by the specialist from your body surface area, kidney function and blood counts. To reduce side effects you must take Folic Acid tablets daily and have Vitamin B12 injections, starting before the first dose, plus a steroid such as Dexamethasone around each infusion, exactly as prescribed.
Interactions
- NSAIDs such as Ibuprofen can raise Pemetrexed levels in people with reduced kidney function; your doctor may ask you to stop them for a few days around each dose.
- Medicines that affect the kidneys (for example some antibiotics) may increase side effects.
- Live vaccines should be avoided during treatment.
Contraindications
- Allergy to Pemetrexed.
- Breastfeeding.
- Use with the yellow fever vaccine.
- Severe kidney impairment (generally not used).
Side Effects
Common side effects include tiredness, nausea, vomiting, loss of appetite, mouth sores, rash, diarrhoea or constipation, and low blood counts (which increase the risk of infection, anaemia and bleeding). Kidney function may be affected.
Get urgent medical help if you have fever of 38°C or above, chills or other signs of infection, unusual bleeding or bruising, severe skin rash with blistering or peeling, shortness of breath or cough that is new or worsening, very little urine, or severe diarrhoea.
Pregnancy and Lactation
Pemetrexed can harm an unborn baby. Women should use effective contraception during treatment and for 6 months after; men should use contraception during treatment and for 3 months after. Do not breastfeed during treatment and for at least 1 week after the last dose.
Precautions and Warnings
- Blood counts and kidney and liver tests are done before each cycle.
- Do not miss the Folic Acid and Vitamin B12 doses; they make treatment safer.
- Tell your doctor if you have had radiotherapy, as skin reactions in treated areas can occur.
- Fluid around the lungs or abdomen may need draining before treatment.
Overdose
Overdose mainly causes very low blood counts, infection, mouth sores and diarrhoea. It is managed in hospital, and the antidote Leucovorin (Calcium Folinate) may be given.
Therapeutic Class
Antineoplastic (cancer chemotherapy), antifolate antimetabolite.
Storage
Hospital medicine: store as directed on the pack, usually below 30°C, away from light. It is prepared and given by trained staff.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.
All brands of Pemetrexed