Antivert
Polarographic determination of antihistamines by complexation with Cd(II).

Temizer A, Ozaltin N.

the polarographic behavior of the complexes formed by Cd(II) ion with ethanolamine derivative antihistamines such as diphenhydramine hydrochloride, dimenhydrinate, and chlorphenoxamine hydrochloride was studied. Antihistamines form spontaneous complexes with Cd(II) ion in the presence of KNO3. In addition, pH 8.00 borate buffer was added to increase the differential pulse polarogram peak height, and tetraalkyl ammonium salts were added to increase the linear range. The method of determination developed has been applied to commercial tablet, capsule, elixir, and injection forms of ethanolamine derivative drugs and has been compared with official methods.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3700330&dopt=Abstract dimenhydrinate meclizine Antivert



Antivert
Clinical evaluation of a dry chemistry strip theophylline assay.

Cheung CM, Soldin SJ.

In this dry chemistry strip immunoassay, flavin adenine dinucleotide (FAD) conjugated theophylline competes with theophylline in the sample for binding to a specific monoclonal antibody. Unbound conjugate can then activate apoglucose oxidase, the activity of which is coupled to a peroxidase chromogenic reaction that allows kinetic monitoring by reflectance photometry. Thirty microliters of diluted sample is placed onto the reagent pad. The strip is inserted into the analyzer, and a digital readout appears 80 s later. Within-run precision was 4.5% based on patient duplicates. Between-day precision was 7.6% at 10 mg/L (n = 29) and 4.5% at 20 mg/L (n = 27). The assay was linear to at least 35 mg/L. There was good agreement between the test method and fluorescence polarization immunoassay: y (test) = -0.2865 + 1.085x (reference), n = 79, r = 0.980, Syx = 1.64. The assay showed good specificity except in patients receiving dimenhydrinate or suffering from renal failure. This system of assay provides reliable measurement of theophylline and will allow easy accessibility to this measurement for physicians working in emergency departments or private offices.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3726936&dopt=Abstract dimenhydrinate meclizine Antivert



Antivert
The effects of TTS-scopolamine, dimenhydrinate, lidocaine, and tocainide on motion sickness, vertigo, and nystagmus.

Pyykko I, Padoan S, Schalen L, Lyttkens L, Magnusson M, Henriksson NG.

The effects of TTS-scopolamine, dimenhydrinate, lidocaine, and tocainide on motion sickness and vertigo and on caloric and postrotatory nystagmus were evaluated in healthy volunteers. TTS-scopolamine was administered transdermally (delivering approximately 10 micrograms X h-1 scopolamine base) and 100 mg dimenhydrinate orally. Lidocaine and tocainide were administered intravenously (average plasma concentration of lidocaine 6 mol X L-1 and of tocainide 20 mol X L-1). TTS-scopolamine and dimenhydrinate significantly reduced vertigo induced by calorization of the ears, nausea provoked with Coriolis maneuvre, and nystagmus in caloric and rotatory tests. During treatment with lidocaine and tocainide no alleviation of vertigo and nausea was observed. Caloric nystagmus was reduced but rotation induced nystagmus was virtually unchanged. Presumably the motion sickness drugs act at the brain stem where TTS-scopolamine and dimenhydrinate have their target cells in the vestibular nuclei. Furthermore, the alleviation of motion sickness was linked to a decline of nystagmus. Lidocaine and tocainide, the action of which in vertigo and nausea in patients is proposed to be on the vestibular end organs and the supratentorial brain structures, consistently failed to alleviate motion sickness.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3929760&dopt=Abstract dimenhydrinate meclizine Antivert



Antivert
Longitudinal change in the treatment of nausea and vomiting of pregnancy in Ontario.

Lee J, Einarson A, Gallo M, Okotore B, Koren G.

The Hospital for Sick Children, Toronto, Canada.

BACKGROUND: Health problems associated with untreated nausea and vomiting of pregnancy (NVP) include maternal weight loss, dehydration, and electrolyte and acid-base disturbances. Negative social consequences include the deterioration of domestic, social and occupational function of the affected women. In 1994 it was documented that most physicians in Ontario tended not to treat women with NVP pharmacologically. PURPOSE: To investigate the longitudinal change in therapeutic practice of physicians, with respect to the treatment of NVP. SUBJECTS AND METHODS: A questionnaire was distributed to a randomly selected sample of physicians that included community-based family physicians, hospital-based family physicians, obstetricians and physicians who called the Motherisk Program for information. The participants were questioned about their choices in the pharmacological treatment of NVP. The data from the survey were compared with those from a previously published survey conducted in 1994. RESULTS: In 1999, 90.2% of physicians surveyed reported to have used pharmacological means to treat NVP. In 1999, 95% of the physicians surveyed reported to have prescribed doxylamine succinate-pyridoxine hydrochloric acid (Diclectin), and 11% prescribed dimenhydrinate (Gravol) to treat NVP. These results are significantly different from those found in 1994 (90% prescribed Gravol as the first choice). CONCLUSIONS: In 1999, temporally related to various educational efforts, physicians offered treatment for NVP more readily, including the drug recommended by the regulatory agency. These changes may explain in part the recently documented decrease in hospitalizations due to NVP in Canada.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11118967&dopt=Abstract dimenhydrinate meclizine Antivert