ABSTRACT
WHAT IS KNOWN AND OBJECTIVE: Studies indicate that there is an increased serum concentration of amlodipine (a calcium channel blocker used to treat hypertension and angina) in patients having mutant multidrug resistance 1 (MDR1) gene. Hence, genetic factors may play a very significant role in amlodipine-induced complications including gingival enlargement. CASE DESCRIPTION: Three patients with amlodipine-induced gingival enlargement showed improvement following drug substitution of amlodipine with enalapril (an angiotensin-converting enzyme inhibitor) and non-invasive periodontal therapy. Using allele-specific polymerase chain reaction, single nucleotide polymorphism of MDR1 gene of heterozygous mutant type (CT genotype) was identified in all three cases. WHAT IS NEW AND CONCLUSION: Drug-induced complications can potentially be a result of genetic factors, in combination with various local and systemic factors. Identifying genetic polymorphisms early might help predict adverse reactions and determine prognosis.
