Approved Anticonvulsant Drugs

Phenobarbital (Figure 1) is a classical barbiturate and has been used as an AED for nearly 100 years. It produces its effects by modulating GABAa receptor function. It is superior to other barbiturates in being able to elicit anticonvulsant effects at doses below those that produce sleep although it is still sedating. Mephobarbital is the N-methyl analog of phenobarbital which functions as prodrug of the latter due to N-demethylation in the hepatic endoplasmic recticulum. Phenytoin is an orally...

Disease State

6.29.1.1 Epidemiology and Socioeconomic Burden Irritable bowel syndrome (IBS), characterized by abdominal pain or discomfort associated with altered bowel habits, is one of the most prevalent disorders of the gastrointestinal (GI) tract. Estimates of the prevalence of IBS in Western countries typically range from 10 to 15 ,1-5 although the prevalence in the United States has been estimated to be as high as 20 .5'6 Differences in these estimates probably result from the use of different...

Dxi

GABA systems, and their precise mechanism of action remains undefined and controversial.136'137 Some reports indicate that gabapentin and pregabalin bind with high affinity to the a2S subunit of voltage-dependent calcium channels but no robust effects have been demonstrated on calcium channel function. Additionally, they are required to be substrates for an amino acid transporter to produce in vivo efficacy, presumably to allow their efficient transit as polar molecules across the gut and...

A425619

Figure 8 Novel nonvanilloid TRPV1 receptor antagonists. compounds elicit. The cloning and characterization of the capsaicin-sensitive vanilloid receptor (TRPV1) has greatly enhanced understanding of the mechanism by which vanilloids, acid, and heat may alter nociceptor sensitivity.68 TRPV1 receptors are one member for a larger family of transient receptor potential (TRP) proteins, several member of which have been associated with sensory function including cold (TRPA1, TRPM8) and mechanical...

Kvu

6.30.5.2.4 Modulators of cholinergic neurotransmission There are limited data from animal experiments studying the activity of muscarinic receptor antagonists on the control of the emetic reflex. In the house musk shrew, scopolamine hyoscine (41) was effective in inhibiting motion-induced vomiting. Muscarinic receptor antagonists, e.g., scopolamine, have long been used in clinical practice to control nausea and vomiting but have little or no value in treating or preventing emesis evoked by...

Introduction

It may seem unusual to be reviewing antiemetic and prokinetic agents in the same chapter however, as one explores these two areas of therapy, one encounters similar classes of agents being used to treat both indications e.g., dopamine D2 receptor antagonists . Alternatively, the same receptor system can sometimes be modulated as a therapeutic approach to both indications, with receptor agonists perhaps being utilized in one indication and receptor antagonists in the other e.g., 5HT3 receptors ....