Unmasking the hidden culprits: Excipients in medicines

Adverse drug reactions (ADRs) are a constant concern in the intricate pharmacovigilance world. As vigilant specialists, we diligently monitor the safety profiles of medications, meticulously cataloging the interactions between active pharmaceutical ingredients (APIs) and the human body. However, a lesser-known realm deserves our attention—the impact of excipients on patient safety. Excipients are the unsung heroes of pharmaceutical formulation, aiding in drug stability, absorption, and even patient acceptability. However, these seemingly benign additives can sometimes lead to unexpected ADRs, making it crucial for pharmacovigilance professionals to unravel their mysteries. In this article, we delve into the world of excipients and their role in ADRs, shedding light on the need for increased vigilance in monitoring these often-overlooked components.

The unsung role of excipients

Excipients are essential components of pharmaceutical formulations. These inert substances serve various purposes, such as improving drug solubility, ensuring uniform drug distribution, and enhancing taste or appearance. They help transform APIs into the familiar pills, capsules, syrups, and creams that patients rely on. While excipients are generally considered safe, they are not entirely devoid of risks. Excipient-related ADRs can be elusive and challenging to identify due to several reasons. Some individuals may be hypersensitive or allergic to specific excipients, making them more susceptible to ADRs. For instance, patients with lactose intolerance may experience gastrointestinal discomfort when a medication contains lactose as an excipient. Healthcare providers and patients may need to recognize excipients as the culprits behind ADRs, leading to underreporting. This can hinder the collection of accurate data and delay regulatory action.

Examples of excipient-related ADRs

Lactose: Lactose is a common excipient in many medications. When exposed to lactose-containing drugs, individuals with lactose intolerance can experience gastrointestinal symptoms such as diarrhea, bloating, and abdominal pain.

Sulfites: Sulfites are used as preservatives in certain medications. Some patients may develop allergic reactions, ranging from mild itching to severe anaphylaxis, upon exposure to sulfite-containing drugs.

Tartrazine (Yellow Dye #5): This food coloring agent, sometimes used in drug formulations, has been associated with hypersensitivity reactions, including skin rashes and, in rare cases, bronchospasm.

Sorbitol: Sorbitol is often used as a sweetener and humectant in liquid medications. Excessive amounts can lead to gastrointestinal symptoms such as diarrhea and abdominal cramps.

Findings of DrugCard in the medical literature

In the journal “Cureus,” specialists from the DrugCard platform found an intriguing case involving a patient’s reaction to flavored oral ibuprofen and acetaminophen formulations. This reaction manifested as fixed drug eruptions (FDEs) with bullae formation. The case centered on an 11-year-old girl who displayed FDEs specifically to flavored liquid versions of NSAIDs and Tylenol but not to plain formulations of both. This patient had a history of a prior FDE after consuming flavored Ibuprofen, resulting in bulla formations and a rash spreading over her neck and chest. Two years later, she was administered non-flavored liquid acetaminophen with no adverse reaction and discharged without incident. However, a month later, when given flavored acetaminophen liquid containing various additives, including citric acid, dye (Allura red), glycerin, and others, the patient experienced a burning sensation within three hours at the previously affected sites.

Enhancing pharmacovigilance for excipient-related ADRs

Healthcare professionals should be educated about the potential risks associated with excipients. Encouraging patients to report unusual reactions can also help identify excipient-related ADRs more effectively. Clear and comprehensive labeling of excipients in medications can aid both healthcare providers and patients identify potential triggers of ADRs. Pharmacovigilance specialists should actively collaborate with regulatory agencies to enhance the surveillance of excipient-related ADRs. This includes tracking trends, conducting risk assessments, and establishing guidelines for reporting.

Conclusion

Please do not underestimate the role of excipients in patient safety, even though they may be silent actors in the world of pharmacology. As pharmacovigilance specialists, our duty extends beyond monitoring APIs to encompass the broader spectrum of drug formulation. Acknowledging the potential risks associated with excipients and working collectively to improve awareness and reporting is crucial. This effort can enhance drug safety and ensure patients receive the best possible care without unexpected ADRs caused by these often-overlooked components.