Related Experiment Video
Updated: Jul 11, 2026
10:27
Recognition of Epidermal Transglutaminase by IgA and Tissue Transglutaminase 2 Antibodies in a Rare Case of Rhesus Dermatitis
Published on: December 15, 2011
24.6K
Metformin-Induced Generalized Bullous Fixed-Drug Eruption with a Positive Dechallenge-Rechallenge Test: A Case Report
Bahareh Abtahi-Naeini1,2, Tooba Momen3, Rezvan Amiri4
1Pediatric Dermatology Division of Department of Pediatrics, Imam Hossein Children's Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
Case Reports in Dermatological Medicine
|April 10, 2023
Summary
Metformin can cause rare skin reactions like generalized bullous fixed-drug eruption (FDE). This case highlights the importance of recognizing uncommon metformin side effects for prompt diagnosis and management.
Area of Science:
- Dermatology
- Pharmacology
- Internal Medicine
Background:
- Metformin is a first-line antidiabetic medication globally.
- Cutaneous adverse reactions are known metformin complications.
- Metformin-induced fixed-drug eruption (FDE) is infrequently reported.
Observation:
- A 43-year-old male presented with generalized bullous lesions.
- A positive dechallenge-rechallenge test confirmed metformin as the causative agent.
- The patient exhibited a rare form of generalized bullous FDE.
Findings:
- Discontinuation of metformin led to lesion resolution.
- Treatment involved topical clobetasol propionate, oral prednisolone, and cyclosporine-A.
- The patient remained relapse-free at 6-month follow-up.
Implications:
- Clinicians must consider metformin-induced FDE in patients with unexplained bullous eruptions.
- Awareness of this uncommon adverse drug reaction aids in accurate diagnosis.
- Early recognition and management can prevent disease progression and recurrence.
Related Concept Videos
01:30Drug Toxicity: Allergic Reactions
Drug-related allergies are immune-mediated responses triggered by the administration of pharmacological agents. These hypersensitivity reactions are classified based on the immune mechanisms involved. The four primary types—Type I, II, III, and IV—are mediated by different immunological pathways and exhibit distinct clinical manifestations.Type I Hypersensitivity/ IgE-Mediated Reactions: Immunoglobulin E (IgE) immediately mediates Type I hypersensitivity reactions. Upon initial exposure to a...
01:16Drug toxicity: Idiosyncratic Reactions
Idiosyncratic drug reactions represent abnormal chemical responses that vary significantly among individuals, ranging from extreme sensitivity to low doses to insensitivity to high doses. These reactions often occur due to the drug's covalent binding with serum proteins, forming a foreign hapten that triggers an immunotoxicological response. The variability in drug reactions has a strong pharmacogenetic foundation, with genetic differences crucial in how individuals metabolize drugs. For...
01:26Oral Hypoglycemic Agents: Biguanides and Glitazones
Biguanides, particularly metformin (Glucophage), are insulin sensitizers that enhance glucose uptake, thereby reducing insulin resistance. Unlike sulfonylureas, metformin doesn't prompt insulin secretion, which helps to curb hypoglycemia risk. Metformin is beneficial in treating conditions like polycystic ovary syndrome due to its insulin-resistance reduction capability. The drug's primary action involves curtailing hepatic gluconeogenesis, a significant contributor to high blood glucose levels...
01:12Type I Diabetes I: Introduction
Type 1 diabetes mellitus is a chronic metabolic disorder characterized by an absolute deficiency of insulin resulting from the autoimmune destruction of pancreatic β-cells. Although it can occur at any age, it is most commonly diagnosed in childhood, adolescence, or early adulthood. The loss of insulin production impairs cellular glucose uptake, resulting in persistent hyperglycemia and necessitating lifelong insulin therapy.Autoimmune Destruction of β-CellsThe hallmark of type 1 diabetes is an...
01:19Type I Diabetes III: Clinical Manifestations
Type 1 diabetes mellitus typically presents with rapid-onset symptoms due to the body’s inability to utilize glucose in the absence of insulin. Since insulin is required for glucose uptake into cells, its deficiency leads to hyperglycemia and cellular energy deprivation, resulting in characteristic clinical features.Polyuria and PolydipsiaOne of the earliest, most prominent symptoms is polyuria (excessive urination). When blood glucose concentrations rise above the renal threshold, the kidneys...