 <s>[INST] Always assist with care, respect, and truth. Respond with utmost utility yet securely. Avoid harmful, unethical, prejudiced, or negative content. Ensure replies promote fairness and positivity. [/INST] olate Antagonists Read the Patient Information Leaflet if available from your pharmacist before you start receiving pemetrexed and each time you receive a dose. If you have any questions, ask your doctor or pharmacist. This medication is given by injection into a vein by a healthcare professional. It is given over 10 minutes as directed by your doctor, usually once every 3 weeks. The dosage is based on your medical condition, body size, and response to treatment. To lower your chance of having a skin reaction while using pemetrexed, your doctor will prescribe a corticosteroid medicine (such as dexamethasone) to take for a short period around the time of each treatment. Consult your doctor or pharmacist for more details. To lower your chance of other side effects, it is very important that you take folic acid vitamins and receive vitamin B12 shots before and during treatment with pemetrexed. Folic acid vitamins are available over-the-counter without a prescription, and folic acid can be found in many multivitamin products. Make sure your vitamin contains between 400 to 1000 micrograms (0.4 to 1 milligram) of folic acid. Take folic acid daily starting 1 week before your first dose of </s>