Q:

1/3/2012
If soy antigen levels in soy lecithin and soy oil is not significant would profopol use be safe in soy allergy patient.

A:

Thank you for your inquiry.

As you know from a previous posting (12/19/2011) on our website, there is little evidence that significant soy allergen exists in soy lecithin and soy oil. Therefore, it is usually safe for patients allergic to soy to ingest these substances. This response was given in regards to potential reactions to foods containing soy oil or soy lecithin.

The question is slightly different in that we are speaking of a drug, and the route of administration is injection. And anaphylaxis to propofol presumably related to egg lecithin has been reported. The veracity of this report and the frequency of the possible occurrence of anaphylaxis to propofol on the basis of either egg allergy or soy allergy has been challenged, however.

Since there are no definitive data in this regard, the best I can do to answer your question is to share with you a few of the articles dealing with this issue.

One can only make a judgment call based on reading this information, but the best I can summarize for you is that the weight of evidence favors the safety of administration of propofol to a soy or egg allergic individual, but no definitive statement can be made in this regard based upon a review of the literature as summarized by the abstracts copied below.

Thank you again for your inquiry and we hope this response is helpful to you.

Possible Anaphylaxis after Propofol in a Child with Food Allergy
Ann Pharmacother March 2003 vol. 37 no. 3 398-401
Abstract
Objective: To report a case of anaphylaxis due to propofol in a child with allergies to egg and peanut oil.
Case summary: A 14-month-old boy with a history of reactive airway disease was hospitalized for treatment of respiratory symptoms. The patient had documented allergies to egg, peanut oil, and mold. Within the first few hours after admission, acute respiratory decompensation occurred, and arrangements were made to transfer the patient to our tertiary-care hospital. Prior to transfer, he was emergently intubated under sedation and paralysis with propofol and rocuronium. When emergency air transport arrived, the patient was hypotensive and tachycardic. His symptoms of anaphylaxis were managed throughout the flight and, upon arrival at our institution, the patient was admitted to the Pediatric Intensive Care Unit. He improved over a 5-day hospital course, and his caregivers were instructed to avoid propofol in the future. The patient's anaphylactic reaction following propofol was rated as a possible adverse drug reaction using the Naranjo probability scale.
Discussion: The use of propofol in pediatric patients for procedural sedation has gained increased favor. Since the propofol formulation contains both egg lecithin and soybean oil, its use is contraindicated in patients with hypersensitivities to these components. Several other drugs have a food component, resulting in contraindications and warnings in product labeling.
Conclusions: Propofol should be avoided in patients with allergies to egg and/or soybean oil, if possible. Clinicians should consider the potential for adverse drug events in patients with select food allergies.

Use of propofol in patients with food allergies
A. E. D. Bradley, et al:
Anaesthesia
Volume 63, Issue 4, page 439, April 2008
Abstract
We read with interest the recent correspondence highlighting the inclusion of peanut allergy in the list of contra-indications in the product literature for propofol [1]. The potential for peanut-allergic patients to be sensitive to propofol is due to the fact that soya oil is one of the excipients of propofol, and that cross-reactivity occurs in legume allergy, for example between soya and peanut. However, it is the protein component that is responsible for allergic reactions in these patients, and as the soya oil present in propofol is refined, it is unlikely to contain significant quantities of allergenic particles. In the food industry soya-containing mixed vegetable oil may be sold for consumption without listing soya as an ingredient [2]. The reason for this is that the dose of protein contained in refined soya oil is too small to provoke a reaction when ingested. Although the minimum dose of protein required to trigger a reaction after oral ingestion has been identified, the same is not true of parenteral administration [3].

There is no mention of egg allergy in the product literature for propofol. The main triggers for egg anaphylaxis are three proteins found in egg white: ovoalbumin, ovomucoid and conalbumin. Lecithin, a purified egg phosphatide present in propofol, is not thought to be problematic for patients who are allergic to eggs. Allergic reactions to propofol have been shown to be triggered by the iso-propyl or phenol groups rather than the lipid vehicle [4, 5].

One case report describes an anaphylactic reaction following administration of propofol to a child with multiple food allergies including egg and peanut. However, other drugs including rocuronium had also been administered. Skin prick testing was not performed and the specific causative agent remains unclear [6]. We have spoken to the Medical Information Department at AstraZeneca who informed us that the final decision to use Diprivan in patients with egg allergy remains at the discretion of the individual anaesthetist concerned (personal communication, D. Gupta, AstraZeneca Ltd).

In summary, the negligible protein content of refined soya oil in propofol suggests the drug is unlikely to trigger a reaction in patients with peanut allergy. The fact that the product literature cites this as a contra-indication must, however, be given careful consideration prior to administration. If the clinician decides propofol is unsuitable, inhalational induction of anaesthesia may provide a useful alternative.

Allergic Reactions to Propofol in Egg-Allergic Children
Andrew Murphy, Published online before print April 5, 2011, doi: 10.1213/ANE.0b013e31821b450f A & A July 2011 vol. 113 no. 1 140-144 Abstract
Background: Egg and/or soy allergy are often cited as contraindications to propofol administration. Our aim was to determine whether children with an immunoglobulin (Ig)E-mediated egg and/or soy allergy had an allergic reaction after propofol use.
Methods: We performed a retrospective case review over an 11-year period (1999¨C2010) of children with IgE-mediated egg and/or soy allergy who had propofol administered to them at the Children's Hospital Westmead, Sydney.
Results: Twenty-eight egg-allergic patients with 43 propofol administrations were identified. No child with a soy allergy who had propofol was identified. Twenty-one children (75%) were male, the median age at anesthesia was 2.4 years (range, 1¨C15 years), and the presence of other atopic disease was common (eczema 61%, asthma 32%, peanut allergy 43%). Most children (n = 19, 68%) had a history of an Ig E-mediated clinical reaction to egg with evidence of a significantly positive egg white skin prick test (SPT) reaction (¡Ý7 mm). Two of these had a history of egg anaphylaxis. The remaining children (n = 9, 32%) had never ingested egg because of significantly positive SPT (¡Ý7 mm). All SPTs to egg were performed within 12 months of propofol administration. There was one nonanaphylactic immediate allergic reaction (n = 1 of 43, 2%) that occurred 15 minutes after propofol administration in a 7-year-old boy with a history of egg anaphylaxis and multiple other IgE-mediated food allergies (cow's milk, nut, and sesame). SPT to propofol was positive at 3 mm. No other egg-allergic child reacted to propofol.
Conclusions: Despite current Australian labeling warnings, propofol was frequently administered to egg-allergic children. Propofol is likely to be safe in the majority of egg-allergic children who do not have a history of egg anaphylaxis.

Sincerely,
Phil Lieberman, M.D.

AAAAI - American Academy of Allergy Asthma & Immunology