Pharmacodynamics history

The current case history will focus on the discovery of tegaserod and will summarize the pharmacodynamic effects in the GI tract and its therapeutic efficacy in IBS-C and CC. 

An additional consideration is the safety assessment of agents that will be used for challenge stimuli in the evaluation of pharmacodynamics. In some cases, there is a long history of uneventful clinical use of tests, for example, bronchial challenge with histamine and methacholine. If used in a similar manner, there may be no need to consider performing safety studies in... 

The speciflc clinical use of the numerous available benzodiazepines depends on their individual pharmacokinetic and pharmacodynamic properties. Drugs with a high affinity for the GABAa receptor (alprazolam, clonazepam, lorazepam) have high anxiolytic efficacy drugs with a short duration of action (temazepam) are used as hypnotics to minimise daytime sedative effects. Diazepam has a long half-life and duration of action and may be favoured for long-term use or when there is a history of withdrawal problems oxazepam has a slow onset of action and may be less susceptible to abuse. 

Finally, a good personal drug history often reveals that iatrogenic polypharmacy contributes to ill health, both physical and psychiatric, in elderly patients. Pharmacokinetic and Pharmacodynamic Issues... 

The similar pharmacological profile of selective serotonin reuptake inhibitors and St. John s wort would suggest the potential of a pharmacodynamic interaction due to an additive effect. A case of concurrent use of sertraline and St. John s wort, resulting in mania, was reported for a patient with a history of depression who was prescribed sertraline and who also took St. John s wort against medical advice (58). A similar potentiation of serotonergic effect was reported by Gordon (49). 

Postsynaptic regulation can be considered from two perspectives modulation by the prior history of activity at the primary receptor (which may up- or down-regulate receptor number or desensitize receptors see Chapter 2 Drug Receptors Pharmacodynamics) and modulation by other temporally associated events. 

Csajka, C., Verotta, D. Pharmacokinetic-pharmacodynamic modelling history and perspectives. / Pharmacokinet Pharmaco-dyn 2006, 33 227-279. 

The pharmacokinetics and pharmacodynamics of zaleplon (10 or 20 mg) and zolpidem (10 or 20 mg) have been investigated in a randomized, double-blind, crossover, placebo-controlled study in 10 healthy volunteers with no history of sleep disorder (15). The half-life of zaleplon was significantly shorter than that of zolpidem. Zaleplon produced less sedation than zolpidem at the two doses studied, and the sedation scores in the zaleplon groups returned to baseline sooner than in the zolpidem groups. Zaleplon had no effect on recent or remote recall, whereas zolpidem had a significant effect on both measures. 

Up to this point in our discussion of pharmacokinetics and pharmacodynamics, our discussion has emphasized the body s neurochemical changes in response to Its ingestion of chemical compounds we call drugs. This emphasis is consistent with the content and long history of the research that has been done on pharmacokinetics and pharmacodynamics. However, a more recently developed and much smaller area of research is concerned with possible ethnic and cultural differences in pharmacokinetics and pharmacodynamics (Lin Poland, 1995). 

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