Effect of ranitidine on the pharmacokinetics of triazolam and alpha-hydroxytriazolam in both young (19-60 years) and older (61-78 years) people.
Clin Pharmacol Ther
; 70(2): 126-31, 2001 Aug.
Article
en En
| MEDLINE
| ID: mdl-11503006
ABSTRACT
OBJECTIVE:
This study evaluated the effect of oral ranitidine (75 mg and 150 mg) on the pharmacokinetics of triazolam (0.25 mg) and its major metabolite, alpha-hydroxytriazolam, in both young and older people. Metabolite data were used to distinguish the mechanism of this interaction.METHOD:
This was a randomized, open-label, 3-way crossover study. Eighteen young (19-60 years) and 12 older (61-78 years) men and women were randomly assigned to receive evening doses of triazolam 0.25 mg (1) alone, (2) on the third day of dosing ranitidine 75 mg twice daily for 4 days, and (3) on the third day of dosing ranitidine 150 mg twice daily for 4 days.RESULTS:
In the young group, mean triazolam area under the concentration-time curve from time zero to infinity [AUC(0-infinity)] was 10% and 28% higher after treatment with 75 mg and 150 mg ranitidine, respectively. In the older group, mean triazolam AUC(0-infinity) was 31% and 28% higher after treatment with 75 mg and 150 mg ranitidine, respectively. There was no change in the alpha-hydroxytriazolam/triazolam AUC(0-infinity) ratio in either age group, indicating that neither formation nor elimination of alpha-hydroxytriazolam was affected by ranitidine. There were no changes in the half-life of triazolam or alpha-hydroxytriazolam.CONCLUSION:
Ranitidine increases oral absorption of triazolam in both young and older people. This effect is likely caused by elevation of gastrointestinal pH, allowing for greater absorption of acid-labile triazolam. The difference in this effect between age groups at the lower 75-mg dose of ranitidine suggests that older people may be more sensitive to the antisecretory effect of ranitidine.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Ranitidina
/
Ansiolíticos
/
Triazolam
/
Envejecimiento
/
Antiulcerosos
Tipo de estudio:
Clinical_trials
/
Prognostic_studies
Límite:
Adult
/
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Clin Pharmacol Ther
Año:
2001
Tipo del documento:
Article
País de afiliación:
Estados Unidos