Aphthasol
Protection against fatal endotoxin shock in mice by antihistamines.

Wittig HJ, Cook TJ, Rittmanic T.

Protection against endotoxin shock by antihistamines and similar pharmacologic agents has been reported in the literature. The authors tested the validity of this form of treatment by animal experiments which were conducted in three phases. During the first phase, 10 mice each were treated intravenously with various doses of gram negative endotoxin to determine the dose of endotoxin which would kill 80% of the animals (LD80). This dose was determined to be 36 mg/kg bodyweight. During the second phase, 10 mice each were pretreated with various doses of either diphenhydramine (Benadryl) or of hydroxyzine HCI (Atarax) one hour prior to the administration of the LD80 of endotoxin. It appeared that high doses of diphenhydramine as well as of hydroxyzine were highly fatal to most animals by causing severe convulsions within 3 to 6 hours at doses of 40 or 50 mg/kg. Doses of less than 1 mg/kg appeared to have no protective effect, while doses of 2.5 and of 5 mg/kg, given one hour prior to the LD80 of endotoxin, had some protective value. In the case of diphenhydramine, 60% of the animals survived with 5 mg/kg pretreatment. Hydroxyzine hydrochloride protected 100% of the 10 animals so treated during the initial experiment and 90% during a subsequent experiment, if given 1 hour before the endotoxin. The third phase of this experiment was designed to determine the optimal time at which hydroxyzine needs to be given to protect against fatal endotoxin shock. Given 6 hours before endotoxin, hydroxyzine appeared to protect half of the animals, 1 hour prior to endotoxin, 5 mg/kg of hydroxyzine protected 90% of animals; if given simultaneously, it protected all animals. When hydroxyzine was given 1 hour after endotoxin there was a 70% survival and, if given 3 hours after endotoxin, a 40% survival.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=33549&dopt=Abstract hydroxyzine Atarax



Aphthasol
Sensitive assay for determination of hydroxyzine in plasma and its human pharmacokinetics.

Fouda HG, Hobbs DC, Stambaugh JE.

An assay suitable for hydroxyzine determination in human plasma following therapeutic doses was developed. The method involves GLC and chemical-ionization mass spectrometry of the acetate derivatives of hydroxyzine and of a pentadeuterated analog internal standard. Following administration of 100-mg single oral doses to normal male volunteers, peak plasma concentrations of approximately 80 ng/ml were observed; the half-life of drug removal was approximately 3 hr.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=512901&dopt=Abstract hydroxyzine Atarax



Aphthasol
Chronic urticaria: a Canadian perspective on patterns and practical management strategies.

Sharma JK, Miller R, Murray S.

Division of Dermatology, Department of Internal Medicine, Dalhousie University, Halifax, Nova Scotia, Canada.

BACKGROUND: Chronic urticaria is a common condition and is a source of great frustration to patients. It has been suggested that there may be differences among physicians in their approach to this common clinical entity. OBJECTIVE AND METHOD: A questionnaire was distributed Canada-wide to allergists, dermatologists, and a selection of practitioners with an interest in alternative medicine. The survey included questions on demographics, epidemiology, causative factors, diagnostic methods, therapeutic strategies, follow-up advice, and efficacy of therapies, with emphasis on personal experience. RESULTS: The response rates of allergists and dermatologists were 31% and 36%, respectively. There was wide representation from all regions of Canada and from physicians from all age groups, both genders, different types of practice, and years in practice. The reported incidence per month was 13 and 4 patients for allergists and dermatologists, respectively. The prevalence was 199 and 44 patients by allergists and dermatologists, respectively. Comparison of causative factors showed differences in the experiences of the two groups. Diagnostic investigations were requested in a similar pattern with respect to timing. The specific tests ordered by the groups showing statistical difference were complete blood count (CBC), differential, C4 complement, antinuclear antibodies, and IgE antibody assay. Allergists chose the skin prick test (100%) as the most important allergy test. Dermatologists ranked skin prick (50%), radioallergosorbent test (RAST) (20%), and skin patch (30%) as the most important tests. The top six choices of pharmaceutical therapies chosen by the groups were similar, but in a slightly different order. The responders ranked their personal selection of antihistamines according to effectiveness. Hydroxyzine (Atarax) and cetirizine (Reactine, Allegra) were selected as first and second most effective agents by both groups. The results also show effective experience by both groups with nonsedating and sedating antihistamines. Also, doxepin, ketotifen, and cimetidine are used frequently by both groups. The experience of dermatologists in Canada with respect to other modalities including psoralen ultraviolet A (PUVA) therapy, danazol, chelation, calcium channel blockers, and acyclovir is limited and efficacy is ranked either neutral or ineffective. Allergists reported even less experience with these therapies. CONCLUSION: Allergists and dermatologists across Canada show interesting similarities and differences in their practical approach to the management of chronic urticaria. With the sharing of this information, these two specialties will be better equipped to effectively manage patients suffering from chronic urticaria.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11179931&dopt=Abstract hydroxyzine Atarax



Aphthasol
[Thin-layer chromatographic technic for the semiquantitative determination of hydroxyzine residues in animal material]

[Article in German]

Ackermann H, Kretzschmann F, Kruger S, Lexow B.

The solution behaviour of hydroxyzine in water and chloroform (in the strongly alkaline and the strongly acidic range) is utilized to extract it from animal material and to purify the extract. A concentration of 0.01 p.p.m. is detectable in liver, kidneys and muscular substance. 0.05 p.p.m. may be determined semiquantitatively by visual spot comparison. In milk, the detectable amount is 0.1 p.p.m. and 0.5 p.p.m. can be determined semiquantitatively. The recoveries of low concentrations of hydroxyzine are likely to be lower in milk samples than in organ samples.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=562985&dopt=Abstract hydroxyzine Atarax



Aphthasol
[Critical comments on a case history "a death case involving tilidine" (author's transl)]

[Article in German]

Klapetek J.

The author looks critically at the description of a suicide case involving a barbiturate dose that could not be determined exactly and doses of hydroxyzine and tilidine. Drugs with a short and a medium short duration of action obviously had the greatest effect. There was no description of an investigation of the gastric contents. The concentration of barbiturates in the blood alone was sufficient to cause death. The deceased also took hydroxyzine, and then finally 750 mg tilidine in capsule form. Tilidine's action is relatively slow in onset. The author discusses tilidine's possible contribution to the cause of death and comes to a different conclusion from the authors of the case report, especially as regards the key words "Tilidine--Intoxication". The authors of the case report ought to have called it "A Death Case Involving Barbiturates, Hydroxyzine and Tilidine" rather than giving is such a suggestive title as "A Death Case Involving Tildine". This would have been a more accurate representation of the facts and would have assisted the reader to grasp the complex toxicological situation more clearly.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=580373&dopt=Abstract hydroxyzine Atarax