Lorna Kemble Pregnancy and Birth

224 Immunotherapy

• Start Creating Your Own Family Tree Today
• Get Pregnant Quickly and Naturally Within 2 Months
• The Look Good Feel Great Pregnancy Kit

Pharmacology and toxicology

Allergen immunotherapy (allergy shots) is an antiallergy therapy in which continuously increasing doses of an allergen arc injected sub-cutaneously. This therapy stimulates the production of immunoglobulins that bind the allergen before it can react with the mast cells. After immunotherapy, the allergic reaction on exposure to the allergen will be diminished because less histamine will be released by the mast cells. Immunotherapy is often effective for those allergic patients in whom the symptoms persist despite optimal environmental control and drug therapy. No specific embryo- or fetotoxic effects are to be expected after immunotherapy in pregnancy (Gilbert 2005, Shaikh 1993). However, a maternal anaphylactic reaction can cause hypotension and decreased uterine perfusion, which may result in fetal damage induced by fetal hypoxia (Luciano 1997),

Recommendation. Allergen immunotherapy can be carefully continued during pregnancy in patients who benefit and are not experiencing adverse reactions. Due to the greater risk of anaphylaxis with increasing doses of immunotherapy, and a delay of several months before immunotherapy becomes effective, it is generally recommended that this therapy is not started during pregnancy. For the same reason, doses should not be increased. There is no indication for the termination of pregnancy or additional diagnostic procedures after immunotherapy during pregnancy.