Type I hypersensitivity in an asthmatic child allergic to peanuts: was soy lecithin to blame?
BACKGROUND
Soy lecithin is widely used as an emulsifier, not only in topical skin care products but also in various drugs administered either topically, orally, or intravenously or by inhalation. Patients strongly allergic to soy and/or peanuts can develop an anaphylactic reaction when exposed to soy lecithin.


METHODS
We report a 3-year-old asthmatic boy, allergic to peanuts, who was treated at the emergency department for an exacerbation of asthma following an upper respiratory tract infection. Within an hour after receiving the second of two inhalations of an ipratropium bromide (Atrovent) metered dose inhaler, he developed respiratory distress and generalized urticaria, an adverse event that regressed within 48 hours of withdrawal of the suspected drug. Soy lecithin, contained as an excipient in the metered dose inhaler, was strongly suspected of being responsible for this reaction.


CONCLUSIONS
Drug products containing soy lecithin can cause severe allergic reactions in patients allergic to peanuts or soy. Physicians should be aware that adverse drug reactions can be due to both the active medical component and the excipient ingredients.
Béliveau
Solange
S
Division of Pharmacology, Department of Social and Preventive Medicine, CHU Sainte-Justine and University of Montreal, Montreal, QC, Canada.
Gaudreault
Pierre
P
Goulet
Lise
L
Primeau
Marie-Noëlle
MN
Marcoux
Danielle
D
D010367:Arachis / Q000276:immunology; D001249:Asthma / Q000188:drug therapy* / Q000276:immunology; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry*; D002675:Child, Preschool; D005079:Excipients; D005512:Food Hypersensitivity / Q000209:etiology / Q000276:immunology; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000209:etiology* / Q000276:immunology*; D009241:Ipratropium / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry*; D054709:Lecithins / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology*; D008297:Male; D009330:Nebulizers and Vaporizers; D030262:Soybean Proteins / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology*
D001993:Bronchodilator Agents; D005079:Excipients; D054709:Lecithins; D030262:Soybean Proteins; D009241:Ipratropium