HoG Handbook

Allergic Reactions to Factor Concentrate


It is possible for anyone to have an allergic reaction to any medicine, even after having used it several times before.  Sometimes a person with a bleeding disorder can become sensitive to the factor concentrate he or she receives.  His body makes antibodies which respond to the factor as if it were a harmful foreign substance.  This is called an allergic reaction.

Allergic reactions may happen while the factor is being given or one or two hours later.  How bad the reaction is and what symptoms it causes can vary.  Because an allergic reaction can be bad enough to kill you, an adult should be nearby when a person is taking factor.  That adult should know how to give a medicine to combat the symptoms of an allergic reaction.  One useful medicine to have ready is the antihistamine, Benadryl® (diphenhydramine).  There is more information about antihistamines below.  The bleeding disorder doctor will explain how to take medicine for allergic reactions.  It is important to be sure that whatever medicine is kept on hand has not expired.

Anyone who has a reaction to factor should write down the lot number of the bottles taken.  No other bottles of factor from the same lot number should be used.  Call the HTC.

Note: The use of a different kind of filter needle may lower the chances of having a second allergic reaction.  It may also be helpful to change brands of factor.  The HTC nurse or doctor can advise what to try.

If a person infuses factor too quickly, he may feel flushed or short of breath.  This is not an allergic reaction.  Slowing the speed that the factor goes into the vein will prevent these symptoms.

Other symptoms of infusing too fast are:

  • feeling sick to your stomach (nausea)
  • headache
  • a bitter taste in the mouth or a taste like a menthol cough drop
  • itching and redness around where the needle went in the skin.

Symptoms of allergic reactions and what to do if they occur:

Mild symptoms - Hives, itching, stuffy or runny nose, coughing, fever.

Hives are red roundish welts on the skin and are the most common reaction symptom.  Although these symptoms are likely to go away in a couple of hours, the doctor should be called.  The doctor may prescribe Benadryl® (diphenhydramine).

Moderate symptoms - Hives over a large part of the body, intense itching, swelling of the eyelids or lips.

If moderate symptoms appear, you should stop giving the factor and call the doctor.  Someone should stay with the person who got the factor in case the symptoms get worse.

Severe symptoms - Feeling of tightness in the throat or chest, shortness of breath, chest pain, wheezing, swelling of the face, paleness, dizziness, fainting.

A severe reaction to factor is called anaphylaxis.  It may happen within minutes of getting factor.  The person with anaphylaxis may have trouble breathing or go into shock.  If severe symptoms begin, stop treatment right away and call 911.  Place the patient on his back and raise his legs.

This type of reaction is rare, but since it is so serious, a person should not take factor without someone else present.  It is helpful for those assisting with factor infusion to learn CPR (cardiopulmonary resuscitation).  The Red Cross, Heart Association, and many hospitals teach this life-saving skill.  Anaphylaxis can happen with any drug, not just factor.

About antihistamines

Antihistamines are drugs used to treat allergy symptoms.  One of the most common, Benadryl®, is used to prevent an allergic reaction.  The generic name is diphenhydramine, sometimes written on labels as "DPH."  Most stores sell several different brands.  The pharmacist can help you select the least expensive one.  If a person is likely to react to factor, he can take Benadryl® in liquid or pill form 30 to 60 minutes before infusing.  Anyone who has reacted to factor before should assume he will again.  His doctor can advise him whether or not to begin taking Benadryl® before treatment.

Antihistamines have some disadvantages.  Some people find that they bleed more easily when they take antihistamines.  Antihistamines can affect how you sleep.  They can cause hyperactivity, especially in children.  More commonly with adults, they can make a person drowsy.  Then it is unsafe to drive or use machines and heavy equipment.