Warnings: it is recommended to take Pemetrexed with folic acid and vitamin B12 to reduce treatment-related blood disorders and GI toxicity. The medication can suppress bone marrow function, resulting in abnormal white blood cells (neutropenia), severe decrease of platelets(thrombocytopenia), and decreased healthy red blood cells (anemia).
Pemetrexed should not be administered to patients with severe kidney disease. One patient with severe renal impairment (creatinine clearance 19 mL/min) who did not receive folic acid and vitamin B12 died of drug-related toxicity following administration of the medication alone.
Indications: This medication is for the treatment of certain cancers, such as lung and mesothelioma. It is a chemotherapy that can be used alone or with other medications to stop or slow the growth of cancer.
Certain health care providers can use Pemetrexed to treat other medical conditions non-mentioned in this article if he believes it may be helpful.
Dosage: Pemetrexed is taken by injection into a vein (intravenous, IV), usually associated withCisplatin. The medication is, most of the times, prescribed with folic acid and vitamin B12 to supplement your diet in order to reduce the development of serious side effects.
This medication is given by a healthcare professional, usually once every 3 weeks, for a 10 minute time period. Your dosage will depend on your response to therapy, weight and medical condition.
You should take the folic acid and B12 before starting this medication, as it will reduce your risk for certain side effects. You can find folic acid over the counter in vitamin form. You should find vitamins that contain at least 350 milligrams up to 1000 milligrams. You should start taking it at least 5 to 7 days before you start taking this medication, during treatment and for 3 weeks after you stop receiving Pemetrexed. Your doctor will give you a shot of B12 intramuscularly, usually one week before treatment and once every 9 weeks after the initial treatment.
To reduce the chances of skin reactions while taking this drug, your doctor may prescribe you medication, such as corticosteroids (e.g. dexamethasone) to take for a short period around the time of treatments.
Overdose: In cases of overdose symptoms, your doctor may reduce the dosage or stopping the treatment completely. Therefore, if you experience signs or symptoms of complications (see side effects), contact your doctor immediately.
Missing dose: The medication is administered in hospital, missing dose is basically difficult if you are present for your appointment. If for some reasons you cannot go to the hospital for the treatment, contact your doctor before the date schedule for the injection.
Contraindications: Tell your doctor of all allergies, as you may be allergic to some inactive ingredients in Pemetrexed.
People that have some medical conditions should not use this medication, such as severe kidney disease.You should tell your doctor of all medical history, including decreased bone marrow function (e.g. anemia and leukopenia), liver problems and kidney problems.
Pregnant women should not take this medication, as it may cause birth defects and harm an unborn baby. Breast feeding is not recommended while taking Pemetrexed.
People that take this medication should not receive any immunizations while taking it and avoid people that have recently had the oral polio vaccination.
Mechanism of Action (MOA) : Pemetrexed acts by inhibiting several metabolic processes involved in the synthesis of DNA, and therefore prevents multiplication of cancer cells.
Interactions: Your doctor and pharmacist should be aware of all interactions possible with this medication. Some nonsteroidal anti-inflammatory medications (e.g. aspirin, ibuprofen, and naproxen) as well as probenecid are known to interact with this medication.
If you are prescribed a low-dose aspirin for the control of heart attacks and stroke, you should still continue use of it while taking this medication. The dose is usually between 81-325 milligrams a day.
Side effects: to reduce the occurrence and severity of skin reactions, a corticosteroid is recommended to be administered the day before, the same day and the day after taking Pemetrexed. In general, the dosage is 4 mg of dexamethasone (Decadron) taken by mouth twice a day. In addition, your doctor may recommend you to take folic acid or a multivitamin containing folic acid daily. At least five doses of folic acid must be taken within 7 days before the first dose of Pemetrexed. You should continue taking the supplement during the duration of the treatment and for 21 days following the last day of the therapy.
You may also be prescribed an intramuscular injection of vitamin B12 in the week preceding the first dose of Pemetrexed and once every three cycles. Subsequent injections of vitamin B12 can take place the same day as the therapy.
Taking Pemetrexed tends to damage the bone marrow, which causes a deficiency of white blood cells, red blood cells and platelets. In addition, the toxicity of the drug may cause adverse reaction in most patients. Most common Pemetrexed side effects include:
Contact your health care provider right away if you experience at least one of the following:
- dizziness or faintness
- chest pain and/or cough
- unreasonable bleeding or bruising
- difficulty breathing and/or swallowing
- difficultor altered speech (dysphonia)
- weakness or numbness of an arm or leg
- Pain, numbness, or tingling in the hands or feet.