Prevalence of debrisoquine oxidation phenotypes in glaucoma patients

  title={Prevalence of debrisoquine oxidation phenotypes in glaucoma patients},
  author={L. Salminen and R. Lindberg and H. -. Toivari and R. Huupponen and T. Kaila and E. Iisalo},
  journal={International Ophthalmology},
The oxidation of debrisoquine, a sympatholytic antihypertensive agent, exhibits genetic polymorphism. The debrisoquine/4-OH-debrisoquine metabolic ratio (MR) separates the population to poor (PM, MR>12.6) and extensive (EM, MR<12.6) metabolizers. 5–10% of the caucasians belong to the PM phenotype. The oxidation of many other drugs, like timolol, correlates with the debrisoquine phenotype.We determined the debrisoquine phenotype in 102 glaucoma patients. The majority of the patients was treated… Expand
2 Citations
Ethnic Differences in the Systemic Pharmacology for Ophthalmologists
It is helpful to remember the differences in efficacy or side effects based on ethnicity when considering the utilization of medications used in ophthalmology. Expand


Inhibitory effects of neuroleptics on debrisoquine oxidation in man.
The results suggest a probable competitive inhibition of oxidative metabolism by neuroleptics, a phenomenon of potential clinical importance both in patients with an inherited poor metabolic capacity and in patients receiving other drugs like beta-adrenoceptor blocking agents and tricyclic antidepressants oxidized by the same enzyme system. Expand
Polymorphic drug oxidation in humans.
Two phenotypes, the extensive (EM) and the poor (PM) metabolizers, have been observed in all populations so far investigated and evidence that in the PM phenotype a cytochrome P-450 isozyme is either missing or functionally inadequate is provided. Expand
Debrisoquine oxidation in a Finnish population: the effect of oral contraceptives on the metabolic ratio.
The metabolites of debrisoquine hydroxylation and 4-hydroxydebrisoquin corresponded well with each other indicating the usefulness of the shorter 4 h collection time, and oral contraceptives may change the phenotyping near the metabolic ratio of 12.6. Expand
The Polymorphic Oxidation of β-Adrenoceptor Antagonists
SummaryWide variability in response to some drugs such as debrisoquine can be attributed largely to genetic polymorphism of their oxidative metabolism. Mostβ-blockers undergo extensive oxidation.Expand
A family and population study of the genetic polymorphism of debrisoquine oxidation in a white British population.
A population survey of 258 unrelated white British subjects showed a polymorphism for the 4-oxidation of debrisoquine, and the alleles controlling this polymorphism appear to control the oxidation of other drugs. Expand
Oxidation phenotype and the metabolism and action of beta-blockers
  • M. Lennard
  • Biology, Medicine
  • Klinische Wochenschrift
  • 2005
Variability in response to some drugs such as debrisoquine can be attributed to genetic polymorphism of their oxidative metabolism, which is a major determinant of the metabolism, pharmacokinetics and some of the pharmacological actions of metoprolol, bufuralol and timolol. Expand
Quinidine and the identification of drugs whose elimination is impaired in subjects classified as poor metabolizers of debrisoquine.
The effects of quinidine at a dose of only 50 mg, on the metabolism of a new drug in EM subjects may prove a useful method of assessing the contribution of the debrisoquine 4-hydroxylase isozyme to the elimination of the drug tested. Expand
Pharmacokinetics and beta‐blocking effects of timolol in poor and extensive metabolizers of debrisoquin
We studied the pharmacokinetics and β‐blocking effects of a single, oral 20 mg dose of timolol in six poor metabolizers (PMs) and six extensive metabolizers (EMs) of debrisoquin. The plasma timololExpand
Timolol and atenolol: relationships between oxidation phenotype, pharmacokinetics and pharmacodynamics.
There was a significant correlation between the debrisoquine to 4-hydroxydebrisoquine ratio and the area under the plasma concentration time curve (AUC) for timolol and the mean degree of beta-adrenoceptor blockade was significantly greater in the poor metabolisers than in the extensive metaboliser 24 h after dosing with timoll. Expand
Physiological disposition and metabolism of timolol in man and laboratory animals.
Timolol [3-(3-tert.-butylamino-2-hydroxypropoxy)-4-morpholino-1,2,5-thiadiazole], was rapidly absorbed, metabolized, and effectively excreted in man, rats, and dogs. Peak plasma levels of timolol-14CExpand