 <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]  the number of red blood cells increasing too quickly, usually within the first 3 months of starting treatment. If you have high blood pressure, it should be well controlled before beginning treatment with this medication. Your blood pressure should be checked often. Ask your doctor if you should learn how to check your own blood pressure. If high blood pressure develops or worsens, follow your doctor's instructions about diet changes and starting or adjusting your high blood pressure medication. Lowering high blood pressure helps prevent strokes, heart attacks, and further kidney problems. Keep all lab appointments to have your red blood cell count/hemoglobin level tested regularly to reduce the chance of this side effect. Rarely, this medication may suddenly stop working well after a period of time because your body may make antibodies to it. A very serious anemia can result. Tell your doctor right away if symptoms of anemia return (such as increased tiredness, low energy, pale skin color, shortness of breath). Tell your doctor right away if you have any serious side effects, including: symptoms of heart failure (such as shortness of breath, swelling ankles/feet, unusual tiredness, unusual/sudden weight gain). Get medical help right away if you have any very serious side effects, including: seizures. This </s>