J Korean Med Sci.  2004 Oct;19(5):750-752. 10.3346/jkms.2004.19.5.750.

A Case Report of a Poor Metabolizer of CYP2D6 Presented with Unusual Responses to Nortriptyline Medication

• Lee SY
• Ki CS
• Hong KS
• Kim JW

• KMID: 1733521
• DOI: http://doi.org/10.3346/jkms.2004.19.5.750

Abstract

We present a case with decreased metabolic activity of CYP2D6, a cytochrome P450 enzyme catalyzing the metabolism of nortriptyline (NT). Conventional dosage regimen led to toxic plasma concentration of NT and adverse effects such as dry mouth, constipation, and dizziness in this case with genotype CYP2D6*5/*10B. This case suggests the clinical usefulness of pharmacogenetic testing in individualized dosage adjustments of NT.

Keyword

Nortriptyline; Cytochrome P-450 CYP2D6; Adverse effects; Pharmacogenetics

MeSH Terms

Antidepressive Agents, Tricyclic/*adverse effects/pharmacokinetics
Cytochrome P-450 CYP2D6/*genetics/metabolism
Depression/*drug therapy/genetics
Genotype
Humans
Male
Middle Aged
Nortriptyline/*adverse effects/pharmacokinetics

Figure

• 

  Fig. 1 Long PCR analysis of CYP2D6*5. A 3.2 kb product represents the deletion of CYP2 D6 gene in this patient (Lane 1, DNA size marker; lane 2, positive control; lane 3, negative control; lane 4, this case).

• 

  Fig. 2 Detection of nucleotide changes by sequencing analysis of CYP2D6 gene. This case has CYP2D6*10B allele with C100T (A), C1039T (B), G1661C (C), and G4180C (D) substitution.

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