Determination of serum desipramine and 2-hydroxydesipramine for pharmacokinetic applications by HPLC with ultraviolet detection.

This procedure for measuring desipramine and its 2-hydroxy metabolite in serum at a minimum concentration of 1 micrograms/L involves high-performance liquid chromatography (HPLC), with ultraviolet detection at 214 nm. After desipramine and 2-hydroxydesipramine are extracted from alkalinized serum by a single-step solvent extraction, they are separated by HPLC and quantified with amitriptyline as the internal standard. Desipramine, 2-hydroxydesipramine, and amitriptyline are separated in 6 min. The standard curve is linear (r = 1.000) for both desipramine and 2-hydroxydesipramine concentrations over the range of 1 to 100 micrograms/L, and the assay demonstrates an excellent precision profile, even at low concentrations. Between-run CVs for 20 and 60 micrograms/L controls (n = 20) were 3.9% and 3.6% for desipramine and 3.4% and 3.8% for 2-hydroxydesipramine, respectively. In a pharmacokinetic evaluation of patients with depression, we examined single-dose elimination curves before and after a four-week regimen of desipramine treatment. The results showed that the method's simplicity and high precision render it ideal for pharmacokinetic studies of desipramine.