Next Article in Journal
Oral Complications of Chemotherapy on Paediatric Patients with Cancer: A Systematic Review and Meta-Analysis
Previous Article in Journal
Adverse Childhood Experiences and Empathy: The Role of Interparental Conflict
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Proceeding Paper

Cow’s Milk Protein Allergy: The Hidden Danger of Medicines’ Excipients †

Maria Santo
Maria D. Auxtero
Alexandra Figueiredo
Isabel Margarida Costa
PharmSci Lab-CiiEM, Interdisciplinary Research Center Egas Moniz, Instituto Universitário Egas Moniz, Quinta da Granja, Monte de Caparica, 2829-511 Almada, Portugal
Author to whom correspondence should be addressed.
Presented at the 5th International Congress of CiiEM—Reducing Inequalities in Health and Society, Online, 16–18 June 2021.
Med. Sci. Forum 2021, 5(1), 32;
Published: 21 July 2021
(This article belongs to the Proceedings of The 5th International Congress of CiiEM (IC CiiEM))


In patients with a cow’s milk protein allergy, the presence of these allergens in medicines, even in trace amounts, can trigger serious allergic reactions. The study of milk-related excipient prevalence in 165 antiasthmatic medicines, based on the information included in the Summary of Product Characteristics, revealed the presence of lactose in more than one third of these medicines. Since lactose may suffer cross-contamination with cow’s milk protein, these results are an alert to health professionals.

1. Introduction

Food allergies are increasingly common, as well as a public health issue with a great impact. Cow’s milk protein (CMP) allergy is one of the most common pediatric allergies [1]. CMP allergy may occur at any age. However, it is more prevalent in children under the age of three. In Europe, the reported prevalence ranges from 2% to 7.5% in the first year of life [2]. It is characterized by an immune response to proteins that are present in cow’s milk [1]. The symptoms include cutaneous, gastrointestinal and respiratory effects. It is also one of the most common causes of anaphylaxis in children up to 2 years old [3]. Patients with this allergy should exclude milk from their diet [1]. Even dairy products that do not directly contain CMP can trigger an allergic reaction in sensitive patients due to cross-contamination. The intake of medicines containing milk-related excipients, such as lactose, may originate symptoms in allergic patients. This study aimed to evaluate the prevalence of milk derivatives as excipients in antiasthmatic medicines available in Portugal.

2. Materials and Methods

The presence of milk-related excipients was evaluated in 165 antiasthmatic medicines based on the Summary of Product Characteristics (SmPC). Selection criteria of medicines included: marketing authorization approved in Portugal, with the SmPC available on the human medicinal products database (INFOMED), for adult and/or pediatric use, in any dose or dosage form, branded or generic.

3. Results and Discussion

From a total of 165 medicines studied, 99 included lactose as an excipient, as stated in the SmPC, mainly inhalation powders and tablets (Figure 1a). Lactose was the only allergen derived from milk mentioned in the list of excipients. Regarding the presence of the allergen in generic (N = 17) and branded (N = 148) medicines, there is lactose in both groups (Figure 1b), with a similar prevalence (60.1% and 58.8%, respectively).
This study revealed a high prevalence of lactose (60%) in antiasthmatic medicines, which may represent a high risk to patients allergic to milk. The presence of milk derivatives as excipients in pharmaceutical products could induce an allergic reaction in patients with CMP allergy. Since respiratory symptoms, such as wheezing, shortness of breath, chest tightness, coughing, and breathing difficulties, are common in allergic patients, antiasthmatics are frequently prescribed medicines.
Lactose, although it is not a milk protein, can also trigger adverse reactions in patients with CMP allergy, due to the risk of cross-contamination by traces of CMP [4]. In the pharmaceutical industry, lactose is widely used as an excipient in medicines [5]. It is used in capsules and tablets as a volume expander or for direct compression, and also as a vehicle in dry powder inhalers, facilitating the delivery of the drug down to the smallest airways [5].
It is essential that the presence of food allergens is highlighted in the composition of the medicines, because even in trace amounts, they can trigger serious reactions in allergic patients. It is also imperative that healthcare professionals have easy access to the detailed composition of medicines, in order to provide a safe prescription and counseling.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Data available in a publicly accessible repository, the data presented in this study are openly available in

Conflicts of Interest

The authors declare no conflict of interest.


  1. Meng, C.; Sutherland, A.; Birrueta, G.; Laubach, S.; Leonard, S.; Peters, B.; Schulten, V. Analysis of Allergen-Specific T Cell and IgE Reactivity to Different Preparations of Cow’s Milk-Containing Food Extracts. Cells 2019, 8, 667. [Google Scholar] [CrossRef] [Green Version]
  2. European Medicines Agency—Committee for Medicinal Products for Human Use. Information for the Package Leaflet Regarding Lactose Used as an Excipient in Medicinal Products for Human Use; European Medicines Agency: London, UK, 2018; EMA/CHMP/186428/2016.
  3. Anagnostou, K. Anaphylaxis in Children: Epidemiology, Risk Factors and Management. Curr. Pediatr. Rev. 2018, 14, 180–186. [Google Scholar] [CrossRef] [PubMed]
  4. Spiegel, W.A.; Anolik, R. Lack of Milk Protein Allergic Reactions in Patients Using Lactose Containing Dry Powder Inhalers (DPIs). J. Allergy Clin. Immunol. 2010, 125, AB69. [Google Scholar] [CrossRef]
  5. Mill, D.; Dawson, J.; Johnson, J.L. Managing acute pain in patients who report lactose intolerance: The safety of an old excipient re-examined. Ther. Adv. Drug Saf. 2018, 9, 227–235. [Google Scholar] [CrossRef] [PubMed] [Green Version]
Figure 1. Presence of lactose as excipient according to: (a) dosage form; (b) generic or branded.
Figure 1. Presence of lactose as excipient according to: (a) dosage form; (b) generic or branded.
Msf 05 00032 g001
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Share and Cite

MDPI and ACS Style

Santo, M.; Auxtero, M.D.; Figueiredo, A.; Costa, I.M. Cow’s Milk Protein Allergy: The Hidden Danger of Medicines’ Excipients. Med. Sci. Forum 2021, 5, 32.

AMA Style

Santo M, Auxtero MD, Figueiredo A, Costa IM. Cow’s Milk Protein Allergy: The Hidden Danger of Medicines’ Excipients. Medical Sciences Forum. 2021; 5(1):32.

Chicago/Turabian Style

Santo, Maria, Maria D. Auxtero, Alexandra Figueiredo, and Isabel Margarida Costa. 2021. "Cow’s Milk Protein Allergy: The Hidden Danger of Medicines’ Excipients" Medical Sciences Forum 5, no. 1: 32.

Article Metrics

Back to TopTop