Neulastin Side Effects

Neulasta is the trade name of pegfilgrastim, a drug marketed by Amgen and sometimes prescribed to cancer patients while undergoing chemotherapy, and is designed to aid in the prevention of infection as a result of neutropenia. Strong chemotherapy can kill infection-fighting agents within the normal human immune system known as neutrophils, resulting in neutropenia. This leads to an increased incidence of infection. Neulasta works to increase production of neutrophils in the body. Side effects from the use of Neulasta range from mild to extremely severe.

Common Side Effects

• The most common side effects of using Neulasta is a deep ache in the bones. This is typically not serious and the pain can be relieved by using a typical, over-the-counter non-aspirin pain reliever such as acetaminophen. According to the manufacturers of the drug, this occurs in just over 30% of cases where patients were using Neulasta. Other common side effects include muscle pain, headaches, and joint pain. Less common but still present are swelling or water retention in the ankles and feet, and constipation.

  Some side effects that occurred in conjunction to chemotherapy include hair loss, diarrhea, and fever, but it is not clear if this was a result of the chemotherapy itself, or the administration of Neulasta.

Severe Side Effects

• Neulasta trials have reported several extremely severe side effects. They are very infrequent, but did occur in trials, and should be considered before taking Neulasta.

  Perhaps the most dangerous is an enlarged or ruptured spleen, which generally presents as abdominal which is sometimes accompanied by shoulder pain. A ruptured spleen is an extremely dangerous situation, and will result in death if it is not immediately treated. Another severe side effect reported in trials is a condition known as acute respiratory distress syndrome (ARDS), where a buildup of fluid occurs in the air sacs of the lungs, resulting in not enough oxygen entering the bloodstream while breathing. Symptoms of ARDS include shortness of breath, rapid, shallow breathing, and low blood pressure.

Allergic Reactions

• Allergic reactions to Neulasta are not very common, but can occur, and range from very mild to extremely severe. Symptoms of an allergic reaction include hives, wheezing, difficulty breathing, and localized swelling around the mouth and eyes. Most allergic reactions in trials occurred upon injection of the drug, although more severe reactions such as anaphylaxis may take several days to fully manifest. As with any severe allergic reaction, the patient should immediately contact her physician and get to a hospital immediately.

Situational Side Effects

• Neulasta was never tested for use with pregnant or breastfeeding women, and it is not known what side effects may occur as a result of pregnancy, although it has led to adverse side effects in rabbit studies. It is possible that some of the drug can cross the placental barrier into a developing fetus. It is unknown whether Neulasta can get into human breast milk.

  In patients with sickle cell anemia, severe flareups of the condition, sometimes leading to death, can occur as a side effect of taking Neulasta. As a result, it is not recommended that Neulasta be prescribed to patients with sickle cell anemia.

  If the patient is taking Lithium, there is a chance it may increase the occurrence and intensity of side effects, and the doctor should be informed of all drugs, vitamins, and supplements that are being taken prior to the administration of Neulasta.

Neulasta in Children

• Amgen, the makers of Neulasta, state that Neulasta should not be administered to infants, children, or adolescents with a body weight of under 10 pounds (45kg), as the effectiveness of the drug as well as the prevalence and severity of side effects were not tested n FDA approval studies and trials. However, according to a 2007 study from France, Neulasta was well-received by children undergoing chemotherapy for cancer, and was "safe and well-tolerated" by those children participating in the trial.