Erythropoietin Facts Brand names (manufacturers): Epogen (Amgen); Procrit (Amgen, Ortho-Biotech)

Type of drug: Antianemia
Ingredient: Erythropoietin
Dosage form: Injection (2,000 units, 3,000 units, 4,000 units, 10,000 units, 20,000 units, or 40,000 units per 1-mL of solution with albumin)
Storage: Store in the refrigerator in the original vial, and protect from light. Do not freeze or shake the vial.

Erythropoietin is used to increase the number of red blood cells in the body in patients with anemia due to renal failure and dialysis or from chemotherapy for certain types of cancers. This drug stimulates the production of red blood cells in the body through a process called erythropoiesis. In patients with chronic renal failure or those receiving certain types of chemotherapy, the process of erythropoiesis is impaired. Erythropoietin is produced using recombinant technology, a method that does not involve the use of any human blood products.

EPO is sold in recombinant form (rhEPO) for injection. It usually is packaged as a lyophilized (freeze dried) powder that is reconstituted with sterile water before injection. One popular form is called Epogen(r), and it is made for subcutaneous usage. A starting dosage is typically 20 i.u. per kilogram bodyweight, 3 times/week. After two to four weeks, a maintenance dose of 20 i.u. /kg BW can be taken once a week.

EPO use can be very dangerous if the user allows their hematocrit to creep too high. The ideal hematocrit for athletic performance is thought to be 55 (expressed in percent). Levels above this can result in "sludging" of the blood, which reduces microcirculation. This is counterproductive to oxygen transport. Additionally, at high hematocrit levels one is at greater risk for deadly vascular events such as stroke, especially if he/she becomes dehydrated during competition (which increases hematocrit even further).

In addition to increasing aerobic efficiency through greater oxygen transport in the blood, there is some evidence suggesting EPO may also have anabolic effects. EPO has been shown in rat studies to substantially increase weight gain and injury repair after surgery. Furthermore, EPO receptors are present on myoblasts (immature muscle cell progenitors) and may have a potential in muscle development and repair.

Side Effects

Minor: Diarrhea, dizziness, headache, itching, muscle aches and pains, nausea, pain at the site of injection, tiredness, or vomiting. These side effects should diminish or disappear as your body adjusts to the medication.

To avoid dizziness when you stand, contract and relax the muscles in your legs for a few moments before rising. Do this by pushing one foot against the floor while raising the other foot slightly, alternating feet so that you are "pumping" your legs in a pedaling motion.

Major: Tell your doctor about any side effects that are persistent or particularly bothersome. IT IS ESPECIALLY IMPORTANT TO TELL YOUR DOCTOR about chest pain; difficulty breathing or shortness of breath; feelings of warmth, pain, or swelling in the legs or hands; palpitations; or seizures.

Interactions

If used properly, erythropoietin should not interact with other medications. However, BE SURE TO TELL YOUR DOCTOR about any medication you are currently taking.

Warnings
Erythropoietin may increase your blood pressure. Monitor your blood pressure regularly while taking this medication.

To make sure this medication is working properly, it is important that blood tests are done to check for anemia while you are being treated with the drug.

Tell your doctor about any unusual or allergic reactions you have had to any medications, especially to erythropoietin, darbepoetin, or any other medication.

Before having surgery or any other medical or dental treatment, be sure to tell your doctor or dentist that you are taking this medication.

Be sure to tell your doctor if you are pregnant. The effects of this medication during pregnancy have not been thoroughly studied in humans. It is also not known if erythropoietin passes into breast milk in humans, so be sure to tell your doctor if you are breast-feeding an infant.