Simultaneous determination of paracetamol, dextromethorphan, chlorpheniramine, pseudoephedrine and major impurities of paracetamol and pseudoephedrine by using capillary electrophoresis

Abstract A capillary electrophoresis method was developed for the first time and optimized for the determination of paracetamol, pseudoephedrine, dextromethorphan, chlorpheniramine, 4-aminophenol and ephedrine in tablet formulation. Optimum electrophoretic conditions were achieved by using a background electrolyte of 75 mmol L-1 sodium borate buffer at pH 8.0, a capillary temperature of 30°C, a separation voltage of 30 kV and a pressure injection of the sample at 50 mbar for 10 s. Calibration graphs showed a good linearity with a coefficient of determination (R2) of at least 0.999 for all compounds. Intraday and interday precision (expressed as relative standard deviation (RSD) %) were lower than 1.39% for capillary electrophoresis method. The developed method was demonstrated to be simple and rapid for the determination of paracetamol, pseudoephedrine, dextromethorphan, chlorpheniramine, 4-aminophenol and ephedrine in tablet formulation providing recoveries in the range between 99.62 and 100.57% for all analytes.

Colestasis intrahepática del embarazo: forma de presentación temprana y relación con la infección por el virus de la hepatitis C: reporte de casos / Intrahepatic cholestasis of pregnancy: early presentation and relationship with infection by the hepatitis C virus: case reports / Colestase intra-hepática da gravidez: forma de apresentação precoce e sua relação com a infecção por vírus da hepatite C: relato de casos

Se describe los casos de tres pacientes a quien se les realiza diagnóstico de colestasis intrahepática del embarazo (CIE) de aparición temprana. En dos de ellos el diagnóstico se relacionó con infección por el virus de la hepatitis C (VHC). Reconocer que esta enfermedad puede presentarse de manera temprana en el embarazo y su relación con la infección por el VHC es fundamental para hacer un diagnóstico oportuno de ambas enfermedades y tomar las conductas terapéuticas adecuadas, mejorando así el pronóstico materno y fetal.

It is of great importance to acknowledge that this disease can occur early in pregnancy and that its relationship with HCV infection is a key point for a prompt diagnosis, allowing taking timely appropriate therapeutic decisions, aimed at improving the fetal prognosis.

Descrevemos os casos de três pacientes com diagnóstico de colestase intra-hepática da gravidez de início precoce. Em dois deles o diagnóstico estava relacionado à infecção pelo vírus da hepatite C (VHC). Reconhecer que esta doença pode se manifestar precocemente na gravidez e sua relação com a infecção pelo VHC é fundamental para fazer um diagnóstico oportuno de ambas as doenças e assumir condutas terapêuticas adequadas, melhorando assim o prognóstico materno e fetal.

Evaluation of the bioequivalence of two formulations containing the combination of 400 mg of acetaminophen (paracetamol), 4 mg of phenylephrine and 4 mg of chlorpheniramine in capsules: open-label, three-way crossover study, partially replicated in healthy volunteers of both sexes

This study was carried out in order to compare the relative bioavailability of two different formulations containing 400 mg of acetaminophen + 4 mg of phenylephrine hydrochloride + 4 mg of chlorpheniramine maleate, Test formulation (Cimegripe®) and Reference formulation (Resfenol®) in 84 healthy volunteers of both sexes under fasting conditions. The study was conducted in a single dose, randomized, open-label, crossover 3-way and partially replicated. The tolerability was evaluated by the monitoring of adverse events and vital signs, results of clinical and laboratory tests. Plasma concentrations were quantified by validated bioanalytical methods using the ultra-performance liquid chromatography coupled to tandem mass spectrometry. The Cmax, Tmax, AUC0-t, AUC0-inf, T1/2 and Kel pharmacokinetic parameters were calculated from these obtained concentrations. The 90% confidence intervals were constructed for the ratio reference/test from the geometric average of the Cmax and AUC parameters which were comprised between 80% and 125%. Only the Cmax parameter of the phenylephrine was applied the scaled average bioequivalence due to the intraindividual coefficient of variation > 30% obtained, thus extending the acceptance limits of the interval. It can be concluded that the two formulations were bioequivalent in terms of rate and absorption extent and thus interchangeable

Anaphylaxis to Chlorpheniramine Maleate and Literature Review

Chlorpheniramine maleate is commonly used antihistamine. Since antihistamines are the main therapeutic agents for symptomatic treatment of urticaria, anaphylaxis to antihistamines may lead to errors in diagnosis and treatment. We report a case of anaphylaxis induced by chlorpheniramine maleate confirmed by intradermal test. A 35-year-old female experienced history of anaphylaxis after intramuscular injection of chlorpheniramine maleate. Skin prick test was negative, but intradermal test was positive. Patient also experienced mild dizziness after intradermal test and refused to perform any further evaluation such as oral challenge test. Anaphylaxis for chlorpheniramine maleate is very rare but should be considered.

Púrpura por Strongyloides stercoralis en un paciente inmunocompetente / Purpura due to Strongyloides stercoralis in an immunocompetent patient

Resumen La infección por Strongyloides stercoralis es una parasitosis frecuente en las regiones tropicales y subtropicales, incluyendo la Amazonía peruana. En pacientes con inmunocompromiso, las manifestaciones clínicas son variadas y es frecuente la diseminación sistémica de la enfermedad, con compromiso de diversos órganos. Las manifestaciones cutáneas son infrecuentes y se describen en pacientes con algún grado de inmunosupresión. Se presenta el caso de un paciente inmunocompetente que desarrolló una púrpura reactiva por una infección por Strongyloides stercoralis crónica. Ante ello, es posible el compromiso cutáneo en pacientes inmunocompetentes con reagudización sistémica por este parásito.

Infection with Strongyloides stercoralis is a common parasitic infection in tropical and subtropical regions, including the Peruvian Amazon. The clinical manifestations are varied in patients with immunocompromised disease, and the systemic spread of the disease is frequent, compromising different organs and systems. Cutaneous manifestations are infrequent, being described in patients with some degree of immunosuppression. We present the case of an immunocompetent patient who developed a reactive purpura due to chronic Strongyloides stercoralis infection. Thus, skin involvement is possible in immunocompetent patients with systemic exacerbation due to this parasite.

Bepotastine-induced urticaria, cross-reactive with other antihistamines

Second-generation antihistamines are widely prescribed for the control of symptoms of allergic inflammation such as itchy hives, coryza, and itchy eyes. In rare circumstances, these drugs might provoke allergic inflammation. Hypersensitivity to bepotastine besilate, a second-generation antihistamine has never been reported. A 17-year-old schoolgirl, whose paroxysmal itchy hives had been controlled with bepotastine, experienced aggravation of the hives. An oral provocation test confirmed her hypersensitivity to bepotastine and cross-reactivity to levocetirizine. She showed no reaction to chlorpheniramine, ketotifen, or olopatadine among the 13 antihistamines tested. While searching for an antihistamine to control her itchy hives, we found that she also exhibited cross-reactivity to various antihistamines with different chemical structures from that of bepotastine, which is not predicted according to the chemical classification of antihistamines. We report a case of hypersensitivity to bepotastine besilate in a patient with chronic spontaneous urticaria.

Do pediatric medicines induce topographic changes in dental enamel?

Abstract The purpose of the present study was to evaluate the effect of common pediatric liquid medicines on surface roughness and tooth structure loss and to evaluate the pH values of these medicines at room and cold temperatures in vitro. Eighty-four bovine enamel blocks were divided into seven groups (n = 12): G1-Alivium®, G2-Novalgina®, G3-Betamox®, G4-Clavulin®, G5-Claritin®, G6-Polaramine® and G7-Milli-Q water (negative control). The pH was determined and the samples were immersed in each treatment 3x/day for 5 min. 3D non-contact profilometry was used to determine surface roughness (linear Ra, volumetric Sa) and the Gap formed between treated and control areas in each block. Scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) were also performed. The majority of liquid medicines had pH ≤ 5.50. G1, G4, and G5 showed alterations in Ra when compared with G7 (p < 0.05). According to Sa and Gap results, only G5 was different from G7 (p < 0.05). Alteration in surface was more evident in G5 SEM images. EDS revealed high concentrations of carbon, oxygen, phosphorus, and calcium in all tested groups. Despite the low pH values of all evaluated medicines, only Alivium®, Clavulin®, and Claritin® increased linear surface roughness, and only Claritin® demonstrated the in vitro capacity to produce significant tooth structure loss.

A Case of Bilateral Acute Angle Closure Attack Induced by Common Cold Medication

PURPOSE: The authors report a case of bilateral simultaneous acute angle closure attack following administration of an over-the-counter common cold medication (ingredients: chlorpheniramine maleate, phenylephrine hydrochloride, and belladonna alkaloid). CASE SUMMARY: A 67-year-old man visited the emergency room with a sudden onset of bilateral blurred vision and ocular pain accompanied by headache, nausea, and vomiting. He had taken an over-the-counter common cold medication three times per day for three days before the visit. His visual acuity was 0.3 and 0.7 and intraocular pressure (IOP) was 50 mm Hg and 40 mm Hg in right and left eye, respectively. The refraction in manifest refractive test was +0.75 D sph = -0.75 D cyl x 100 in right eye and +1.25 D sph = -1.25 D cyl x 80 in left eye. The anterior chamber depth was three times the corneal thickness in center and less than 1/4 of the corneal thickness in periphery in both eyes on van Herick method. The angles of both eyes were closed on gonioscopy. He was treated with ocular hypotensive medication and miotics followed by withdrawal of common cold medications. After 10 days, bilateral neodymium-doped yttrium aluminium garnet (Nd:YAG) laser peripheral iridotomies were done. During four months of follow-up, there was no recurrence of angle closure attack, and normal IOP was maintained without glaucoma medications. CONCLUSIONS: Common cold medications which are easily accessible can induce acute angle closure attack in those who are predisposed to develop angle closure attacks, hence attention must be taken in those people when taking common cold medications.

Assessment of Potentially Inappropriate Medication Use in Korean Elderly Patients with Parkinson's Disease

OBJECTIVES: The present study assessed the prevalence of the potentially inappropriate medication (PIM) use in Korean elderly patients with Parkinson's disease. In addition, this study examined risk factors that affect PIM use. METHOD: A retrospective, observational study was conducted using Korean National Health Insurance claims database of 2009. PIM use in Parkinson's disease patients aged 65 years or older was examined based on 2012 Beers Criteria. Multivariable logistic regression was conducted to identify risk factors for PIM use. RESULTS: Among 5,277 elderly patients with Parkinson's disease, 88.9% of patients used PIM(s) at least once. The average number of PIM items used per patient was 4.2. PIM use ratio, the proportion of total amount of PIMs to all medications per patient, was 12.6%. Frequently used PIM therapeutic classes were benzodiazepines (32.7%), first-generation antihistamines (19.2%), and prokinetics (17.5%). Individual PIMs most commonly used included chlorpheniramine (11.4%), levosulpiride (10.9%), diazepam (9.0%), and alprazolam (7.6%). Women (odds ratio [OR] 1.14, 95% confidence interval [CI] 1.11-1.16), medical aid (OR 1.18, 95% CI 1.15-1.21), and long-term facilities (OR 2.43, 95% CI 2.22-2.65) were shown to be risk factors associated with PIM use. Of particular, wide variation in PIM use was associated with the types of healthcare facility. CONCLUSION: The PIM prevalence was very high in elderly Parkinson's disease patients. Nationally effective and systematic efforts to identify and prevent PIM use should be made to ensure patient safety and to improve quality of care in the elderly.

Chlorpheniramine-induced anaphylaxis diagnosed by basophil activation test

Chlorpheniramine is a widely prescribed H1-antihistamine for relieving urticaria or histamine-mediated allergic reactions. However, although rare, it may cause immediate hypersensitivity reactions. The diagnosis is usually made by provocation test, but its application is often limited due to comorbidities or potential risk of severe reactions. In those cases, skin tests and basophil activation tests can be considered as additional diagnostic tests for the drug allergy. Here, we report a 33-year-old female with underlying chronic urticaria, who recurrently developed anaphylaxis after chlorpheniramine administration. Intradermal test showed positive responses in the patient at 0.02 mg/mL of chlorpheniramine, but not in healthy controls. Basophil activation test showed significant up-regulation of CD63 and CD203c by chlorpheniramine. The present case reminds the rare but potential allergic risk of chlorpheniramine, and also suggests the potential utility of basophil activation test in making the diagnosis.

Successful administration of iodinated contrast media in a patient with anaphylaxis to multiple contrast media

Although hypersensitivity reactions to iodinated contrast media (ICM) are uncommon, their clinical impacts are considerable because of their wide use and potential fatality. The best way to prevent ICM-induced hypersensitivity is to avoid re-exposure to the ICM. However, ICM use is inevitable in the evaluation of many diseases. A 64-year-old male with renal cell carcinoma presented with anaphylaxis after computed tomography (CT) using iohexol. Intradermal test results were positive to iohexol, iomeprol, and ioversol. The following 3 CT scans using the test-negative agents iopromide, iopamidol, and iobitridol still provoked hypersensitivity reactions despite premedication using intravenous antihistamine and corticosteroid. For the next step, iodixanol, a nonionic iso-osmolar dimer, was tested by intravenous graded challenges in addition to the intradermal skin test, which and was confirmed to be negative. The patient underwent CT scan using iodixanol after premedication with chlorpheniramine 4 mg and methylprednisolone 40 mg, and hypersensitivity reactions did not recur. We report a case of a patient showing hyper reactivity to multiple ICMs despite negative intradermal skin tests, who eventually underwent successful enhanced CT scans after choosing ICM by the graded challenge test.

Bee Pollen-Induced Anaphylaxis: A Case Report and Literature Review

Bee pollen is pollen granules packed by honey bees and is widely consumed as natural healthy supplements. Bee pollen-induced anaphylaxis has rarely been reported, and its allergenic components have never been studied. A 40-year-old male came to the emergency room with generalized urticaria, facial edema, dyspnea, nausea, vomiting, abdominal pain, and diarrhea 1 hour after ingesting one tablespoon of bee pollen. Oxygen saturation was 91%. His symptoms resolved after injection of epinephrine, chlorpheniramine, and dexamethasone. He had seasonal allergic rhinitis in autumn. Microscopic examination of the bee pollen revealed Japanese hop, chrysanthemum, ragweed, and dandelion pollens. Skin-prick with bee pollen extracts showed positive reactions at 0.1 mg/mL (A/H ratio > 3+). Serum specific IgE to ragweed was 25.2, chrysanthemum 20.6, and dandelion 11.4 kU/L; however, Japanese hop, honey-bee venom and yellow-jacket venom were negative (UniCAP(R), Thermo Fisher Scientific, Uppsala, Sweden). Enzyme-linked immunosorbent assay (ELISA) confirmed serum specific IgE to bee-pollen extracts, and an ELISA inhibition assay for evaluation of cross-allergenicity of bee pollen and other weed pollens showed more than 90% of inhibition with chrysanthemum and dandelion and ~40% inhibition with ragweed at a concentration of 1 microg/mL. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and IgE-immunoblot analysis revealed 9 protein bands (11, 14, 17, 28, 34, 45, 52, 72, and 90 kDa) and strong IgE binding at 28-34 kDa, 45 and 52 kDa. In conclusion, healthcare providers should be aware of the potential risk of severe allergic reactions upon ingestion of bee pollen, especially in patients with pollen allergy.

Effect of histamine H1 and H2 receptor antagonists, microinjected into cerebellar vermis, on emotional memory consolidation in mice

This study investigated the effects of histamine H1 or H2 receptor antagonists on emotional memory consolidation in mice submitted to the elevated plus maze (EPM). The cerebellar vermis of male mice (Swiss albino) was implanted using a cannula guide. Three days after recovery, behavioral tests were performed in the EPM on 2 consecutive days (T1 and T2). Immediately after exposure to the EPM (T1), animals received a microinjection of saline (SAL) or the H1 antagonist chlorpheniramine (CPA; 0.016, 0.052, or 0.16 nmol/0.1 µL) in Experiment 1, and SAL or the H2 antagonist ranitidine (RA; 0.57, 2.85, or 5.7 nmol/0.1 µL) in Experiment 2. Twenty-four hours later, mice were reexposed to the EPM (T2) under the same experimental conditions but they did not receive any injection. Data were analyzed using one-way ANOVA and the Duncan test. In Experiment 1, mice microinjected with SAL and with CPA entered the open arms less often (%OAE) and spent less time in the open arms (%OAT) in T2, and there was no difference among groups. The results of Experiment 2 demonstrated that the values of %OAE and %OAT in T2 were lower compared to T1 for the groups that were microinjected with SAL and 2.85 nmol/0.1 µL RA. However, when animals were microinjected with 5.7 nmol/0.1 µL RA, they did not show a reduction in %OAE and %OAT. These results demonstrate that CPA did not affect behavior at the doses used in this study, while 5.7 nmol/0.1 µL RA induced impairment of memory consolidation in the EPM.

Successful desensitization for cytarabine induced anaphylaxis

Cytarabine is a very important chemotherapeutic agent for leukemia and lymphoma patients and is prescribed more frequently than before. Cytarabine-induced delayed-onset hypersensitivity may rarely present as non-IgE mediated anaphylaxis. However, we do not know yet whether desensitization therapy in adults may be effective in cytarabine-induced delayed-onset anaphylaxis. A 78-year-old woman who was diagnosed with acute myeloblastic leukemia had chemotherapy including cytarabine. In spite of premedication with hydrocortisone and chlorpheniramine, the patient had anaphylaxis a few hours after cytarabine infusion. We decided to perform desensitization therapy. After desensitization therapy using a newly designed protocol, the patient was tolerable to cytarabine infusion without hypotension or high fever. Desensitization therapy was successfully performed on an adult patient with delayed-onset anaphylaxis caused by cytarabine.

Analysis of chlorpheniramine in human urine samples using dispersive liquid-liquid microextraction combined with high-performance liquid chromatography

A simple and environmentally friendly microextraction technique was used for determination of chlorpheniramine (CPM), an antihistamine drug, in human urine samples using dispersive liquid-liquid microextraction (DLLME) followed by high performance liquid chromatography with diode array detection (HPLC-DAD). In this extraction technique, an appropriate mixture of acetonitrile (disperser solvent) and carbon tetrachloride (extraction solvent) was rapidly injected into the urine sample containing the target analyte. Tiny droplets of extractant were formed and dispersed into the sample solution and then sedimented at the bottom of the conical test tube by centrifugation. Under optimal conditions, the calibration curve was linear in the range of 0.055-5.5 µg mL-1, with a detection limit of 16.5 ng mL-1. This proposed method was successfully applied to the analysis of real urine samples. Low consumption of toxic organic solvents, simplicity of operation, low cost and acceptable figures of merit are the main advantages of the proposed technique.

Utilizou-se uma técnica de microextração simples e ambientalmente amigável para a determinação de clorfeniramina (CPM), anti-histamínico, em amostras de urina humana, utilizando a microextração dispersiva líquido-líquido (DLLME), seguida por cromatografia líquida de alta eficiência com detecção por arranjo de diodos (HPLC-DAD). Nesse método de extração, mistura apropriada de acetonitrila (solvente dispersor) e tetracloreto de carbono (solvente de extração) foi injetada rapidamente na amostra de urina contendo o analito alvo. As pequenas gotículas de agente de extração foram formadas e dispersas na solução da amostra e, em seguida, sedimentadas no fundo do tubo cônico de ensaio por centrifugação. Em condições ótimas, a curva de calibração foi linear no intervalo entre 0,055 e 5,5 µg mL-1, com limite de detecção de 16,5 ng mL-1. O método proposto foi aplicado com sucesso na análise de amostras de urina reais. Baixo consumo de solventes orgânicos tóxicos, simplicidade de operação, baixo custo e figuras de mérito aceitáveis são as principais vantagens do método sugerido.

H1 but not H2 histamine antagonist receptors mediate anxiety-related behaviors and emotional memory deficit in mice subjected to elevated plus-maze testing

This study investigated the role of H1 and H2 receptors in anxiety and the retrieval of emotional memory using a Trial 1/Trial 2 (T1/T2) protocol in an elevated plus-maze (EPM). Tests were performed on 2 consecutive days, designated T1 and T2. Before T1, the mice received intraperitoneal injections of saline (SAL), 20 mg/kg zolantidine (ZOL, an H2 receptor antagonist), or 8.0 or 16 mg/kg chlorpheniramine (CPA, an H1 receptor antagonist). After 40 min, they were subjected to the EPM test. In T2 (24 h later), each group was subdivided into two additional groups, and the animals from each group were re-injected with SAL or one of the drugs. In T1, the Student t-test showed no difference between the SAL and ZOL or 8 mg/kg CPA groups with respect to the percentages of open arm entries (%OAE) and open arm time (%OAT). However, administration of CPA at the highest dose of 16 mg/kg decreased %OAE and %OAT, but not locomotor activity, indicating anxiogenic-like behavior. Emotional memory, as revealed by a reduction in open arm exploration between the two trials, was observed in all experimental groups, indicating that ZOL and 8 mg/kg CPA did not affect emotional memory, whereas CPA at the highest dose affected acquisition and consolidation, but not retrieval of memory. Taken together, these results suggest that H1 receptor, but not H2, is implicated in anxiety-like behavior and in emotional memory acquisition and consolidation deficits in mice subjected to EPM testing.

Involvement of cross interaction between central cholinergic and histaminergic systems in the nucleus tractus solitarius in regulating carotid sinus baroreceptor reflex / 生理学报

The carotid sinus baroreceptor reflex (CSR) is an important approach for regulating arterial blood pressure homeostasis instantaneously and physiologically. Activation of the central histaminergic or cholinergic systems results in CSR functional inhibitory resetting. However, it is unclear whether two systems at the nucleus tractus solitarius (NTS) level display cross interaction to regulate the CSR or not. In the present study, the left or right carotid sinus region was isolated from the systemic circulation in Sprague-Dawley rats (sinus nerve was reserved) anesthetized with pentobarbital sodium. Respective intubation was conducted into one side isolated carotid sinus and into the femoral artery for recording the intracarotid sinus pressure (ISP) and mean arterial pressure (MAP) simultaneously with pressure transducers connection in vivo. ISP was set at the level of 0 mmHg to eliminate the effect of initial internal pressure of the carotid sinus on the CSR function. To trigger CSR, the ISP was quickly elevated from 0 mmHg to 280 mmHg in a stepwise manner (40 mmHg) which was added at every step for over 4 s, and then ISP returned to 0 mmHg in similar steps. The original data of ISP and corresponding MAP were fitted to a modified logistic equation with five parameters to obtain the ISP-MAP, ISP-Gain relationship curves and the CSR characteristic parameters, which were statistically compared and analyzed separately. Under the precondition of no influence on the basic levels of the artery blood pressure, the effects and potential regulatory mechanism of preceding microinjection with different cholinoceptor antagonists, the selective cholinergic M1 receptor antagonist, i.e., pirenzepine (PRZ), the M2 receptor antagonist, i.e., methoctramine (MTR) or the N1 receptor antagonist, i.e., hexamethonium (HEX) into the NTS on the changes in function of CSR induced by intracerebroventricular injection (i.c.v.) of histamine (HA) in rats were observed. Meanwhile, the actions and possible modulatory mechanism of preceding microinjection with different histaminergic receptor antagonists, the selective histaminergic H1 receptor antagonist, i.e., chlorpheniramine (CHL) or the H2 receptor antagonist, i.e., cimetidine (CIM) into the NTS on the changes in function of CSR resulted from the i.c.v. cholinesterase inhibitor, physostigmine (PHY) were also examined in order to confirm and to analyze effects of cross interaction between central histaminergic and cholinergic systems on CSR. The main results obtained are as follows. (1) Standalone microinjection of different selective cholinergic receptor antagonists (PRZ, MTR or HEX) or different selective histaminergic receptor antagonists (CHL or CIM) into the NTS with each given dose had no effects on the CSR function and on the basic levels of the artery blood pressure, respectively (P > 0.05). (2) The pretreatment of PRZ or MTR into the NTS with each corresponding dose could attenuate CSR resetting resulted from i.c.v. HA in some degrees, which remarkably moved the posterior half range of ISP-MAP relationship curve downwards (P < 0.05), shifted the middle part of ISP-Gain relationship curve upwards (P < 0.05), and increased reflex parameters such as the MAP range and maximum gain (P < 0.05), but decreased parameters such as saturation pressure and intracarotid sinus pressure at maximum gain (P < 0.05). The catabatic effects of pretreatment with MTR into the NTS on CSR resetting induced by i.c.v. HA were more obvious than those with PRZ (P < 0.05), but pretreatment of HEX with given dose into the NTS had no effects on CSR resetting induced by i.c.v. HA (P > 0.05). (3) The effects of pretreatment of CHL or CIM into the NTS with each corresponding dose on CSR resetting made by i.c.v. PHY were similar to those of pretreatment of PRZ or MTR into the NTS on CSR resetting resulted from i.c.v. HA, and the decreasing effects of pretreatment with CHL into the NTS on CSR resetting induced by i.c.v. PHY were more remarkable than those with CIM (P < 0.05). These findings suggest that CSR resetting resulted from either HA or PHY into the lateral ventricle may partly involve the descending histaminergic or cholinergic pathway from the hypothalamus to NTS, which might evoke a cross activation of the cholinergic system in the NTS, via cholinergic M1 and M2 receptors mediation, especially the M2 receptors showing actions, or trigger another cross activation of the histaminergic system in the NTS, by histaminergic H1 and H2 receptors mediation, especially the H1 receptors displaying effects.

A case of levocetirizine-induced fixed drug eruption and cross-reaction with piperazine derivatives

Fixed drug eruption is an uncommon adverse drug reaction caused by delayed cell-mediated hypersensitivity. Levocetirizine is an active (R)-enatiomer of cetirizine and there have been a few reports of fixed drug eruption related to these antihistamines. We experienced a case of levocetirizine-induced fixed drug eruption and cross-reaction with other piperazine derivatives confirmed by patch test. A 73-year-old female patient presented with recurrent generalized itching, cutaneous bullae formation, rash and multiple pigmentation at fixed sites after taking drugs for common cold. She took bepotastine besilate (Talion®) and levocetirizine (Xyzal®) as antihistamine. She took acetaminophen, pseudoephedrine 60 mg / triprolidine 2.5 mg (Actifed®), dihydrocodeinebitartrate 5 mg / di-methylephedrine hydrochloride 17.5 mg / chlorpheniramine maleate 1.5 mg / guaifenesin 50 mg (Codening®) and aluminium hydroxide 200 mg / magnesium carbonate 120 mg (Antad®) at the same time. Patch test was done with suspected drugs and the result was positive with levocetirizine. We additionally performed patch test for other antihistamines such as cetirizine, hydroxyzine, fexofenadine and loratadine. Piperazine derivatives (cetirizine and hydroxyzine) were positive, but piperidine derivatives (fexofenadine and loratadine) were negative to patch test. There was no adverse drug reaction when she was challenged with fexofenadine. We report a case of levocetirizine-induced fixed drug eruption confirmed by patch test. Cross-reactions were only observed in the piperazine derivatives and piperidine antihistamine was tolerant to the patient.

Simultaneous determination of naphazoline hydrochloride, chlorpheniramine maleate and methylene blue in their ternary mixture

Validated spectrophotometric and chemometric methods were developed for determination of Naphazoline Hydrochloride [NAP], Chlorpheniramine maleate [CLO] and Methylene blue [MB] in their ternary mixture. Method A was a spectrophotometric method, where NAP and MB were determined using second derivative [D2] spectrophoto metric method using the peak amplitudes at 299 nm and 337 nm for NAP and MB respectively, while CLO was determined using second derivative ratio [DD[2]] spectrophotometric method using the peak amplitude at 276.6 nm. Method B used the chemometric techniques; principal component regression [PCR] and partial least squares [PLS] for determination of NAP, CLO and MB using the information contained in the absorption spectra of their ternary mixture solutions. The proposed methods have been successfully applied for the analysis of NAP, CLO and MB in their pharmaceutical formulation and the obtained results were statistically compared with the reported methods