Alimta also known as pemetrexed is the first drug ever approved for use in mesothelioma. It was approved following a large trial that compared Alimta/cisplatin with single agent cisplatin. It was found that patients who received the combination had a survival advantage over cisplatin alone. This combination is now considered to be the standard of care for those diagnosed with mesothelioma.
Early in the trial it was found that patients needed to be supplemented with both folic acid and vitamin B-12 to prevent significant side effects.
One week prior to starting chemotherapy with Alimta patients are instructed to take folic acid at a dose ranging between 400-800 micrograms. Standard vitamin preparations in the United States contain 400 micrograms, and we now know that too much folic acid can affect the efficacy of Alimta. We suggest that you take either a multi vitamin containing this amount or a single folic acid tablet which usually is 500microgram. This needs to be continued for 3 weeks after discontinuation of Alimta. Vitamin B-12 1000 micrograms is given by injection every 9 weeks. We suggest that you keep a diary to track this as well as your other medications. Dexamethasone 4 mg is given twice daily the day before the day of and the day following Alimta therapy. It is important to help prevent the skin rash associated with Alimta.
Cisplatin is associated hearing loss and neurotoxicity. It is advised that you inform your doctor if you have hearing loss prior to starting cisplatin and if you notice a change in hearing during your therapy. Neurotoxicity can manifest itself as a change of sensation in your hands and feet and can feel like you are wearing stockings and or gloves. It can also be reported as a painful tingling sensation. You should notify your doctor is this a preexisting condition or if it occurs during therapy.
Nausea and vomiting can occur with this combination and cisplatin also has a reputation for causing delayed nausea and vomiting. I will go into the different medications and classes of drugs to help prevent this in another blog. For the time being it is important to ask for your prescriptions prior to initiating therapy so you will have some on hand when you return home from the clinic. Not every insurance company covers all of the different drugs so it is important to start the process early because if they deny coverage this might take some time to have it overturned or receive a prescription for a different drug. If you have a mail order plan you need advance timing to insure delivery prior to start of chemotherapy.
Some patients will experience a change in their blood counts during therapy. This can result in a low red blood cells which manifest as anemia, a low white count which interferes with your ability to fight infection, and or a low platelet count which hinders your ability to inhibit bleeding. Your doctor will monitor these counts and adjust therapy accordingly.
Both of these drugs require good kidney function. You might be asked to discontinue aspirin, Motrin, Aleve and similar drugs known as nonsteroidal anti-inflammatory drugs (NSAIDS) as they compete for clearance of drugs from the kidneys. Always let your health care provider know what over the counter as well as prescription medications you take.
You will receive this combination in an outpatient setting. You should expect to be there for at least 6 hours as iv hydration is given to protect your kidney function. You will also receive medication to prevent nausea and vomiting prior to therapy. You should eat a light meal prior to chemo and it is suggested that you avoid fried foods. Some patients bring snacks with them or a light lunch as not all centers provide food or beverages. Bring some magazines or a book as it is a long day and it is better to have some distraction. A friend or family member is encouraged but try and limit it to one as the centers become over crowded with too many additional “supporters”. You usually feel great the first evening and that is when you should plan a nice meal. Most patients do not tolerate 8 glasses of water daily but you need to be well hydrated during therapy so monitor your urine if it is light or straw colored you are getting adequate hydration or it becomes dark you need to increase your liquids. If you are unable to eat or keep fluids down your doctor needs to be notified. They will arrange iv hydration in either the inpatient or outpatient setting. Many patients tolerate chemotherapy with mild to moderate symptoms. Fatigue is common and there is no “fighting it” take a nap and when you feel somewhat refreshed resume activity. Your quality of life is important and there are so many strategies to assist those who are having difficulty with therapy. Be your own advocate, let the team know what difficulties you are experiencing as we all are interested in our patients’ well being and will work with you to devise strategies to help you get through this difficult time.
~Mary Hesdorffer, NP
