Amphotericin B can be determined by chemical (HPLC, spectrophotometry) and microbiological (bioas... more Amphotericin B can be determined by chemical (HPLC, spectrophotometry) and microbiological (bioassay) methods. The utilization of both during a stability test can give more detailed information about the activity and concentration change of amphotericin B solutions. Previously published HPLC methods do not lay stress on the separation of by-constituents present in the substance. We have also observed that the bioassay conditions described in the Ph. Eur. 6. are not suitable for the measurement of concentration change experienced during a stability test. The aim of our study was to optimize the chemical and microbiological methods. We have improved the eluent system based on earlier HPLC methods for the separation of the main heptaene and the minor tetraene by-constituents in Fungizone (Bristol-Myers Squibb). The most optimal bioassay conditions were determined where a relatively wide concentration range can be measured. With the improved methods both chemical and microbiological cha...
Recent studies have shown that the presence of fungal cells in the nasal mucosa may play an impor... more Recent studies have shown that the presence of fungal cells in the nasal mucosa may play an important role in the development of chronic rhinosinusitis with nasal polyps. In 2006 a pilot clinical trial was organized by the Department of Otorhinolaryngology, Head and Neck Surgery and the Pharmaceutical Institute of the Medical University of Pécs for the treatment of patients with chronic rhinosinusitis with nasal polyps. In our study we investigated the stability of the 5 mg/ml amphotericin B solutions (Fungizone) with chemical (spectrophotometry) and biological (bioassay) detection. The effect of storage temperature and the addition of 5% glucose was evaluated on the stability of the solutions for three months. The two detection methods showed different results. According to the chemical analysis the samples are considered relatively stable under all observed conditions (loss of concentration is: 14.2% at 20 degrees C and 4.5% at 4 degrees C). The bioassay shows complete loss of ant...
The increasing number of patients taking supplementary products together with prescribed medicine... more The increasing number of patients taking supplementary products together with prescribed medicines has become a new challenge for health care systems. These products may influence therapy outcomes by inducing unwanted effects. Particularly concerning is the potential for harmful interactions between prescribed medicines and supplementary products. The aims of the study were to evaluate supplement use, to identify and analyse potential interactions, and to assess the efficiency of computerised interaction screening. Participants of the study were inpatients and outpatients of a Hungarian university hospital. A cross-sectional point-of-care survey of 200 patients was carried out. Data was collected through personal interviews and a review of the medical records. Drug-drug, drug-supplement and supplement-supplement interactions were analysed with three interaction databases (Lexi-Interact Online, Medscape Drug Interaction Checker and Mediris). Prevalence of supplementary product use, number of medicines and supplementary products per patient, procurement sources of products, number of potentially severe interactions. There was a marked difference between data obtained from patient interviews and the medical records. 85.5 % of the surveyed patients took supplementary products during the 2 weeks prior to the interview. The average number of prescribed medicines and supplementary products were 7.8 and 2.5, respectively. Women were more likely to take supplements than men. There was no significant difference in supplement use between patients under or over 60 years, between inpatients and outpatients and among patients in various wards. 39.4 % of supplementary products were purchased outside a regulated pharmacy environment. Potentially severe drug-supplement interactions were detected with 45.2 % of supplement users; however the majority of interactions were not included in one or the other of the three databases. In addition to that the risk ratings of the same interactions varied greatly between databases. A significant number of patients are exposed to potential drug interactions with supplementary products; however interagreement among interaction databases is poor. Our data suggest that a full medication history should specifically address the intake of supplements.
The insufficient response of patients to antidepressant medications may result from several facto... more The insufficient response of patients to antidepressant medications may result from several factors, including altered drug metabolism. CYP2D6 genotyping may help assess the possible factors that contribute to difficult-to-treat depression. The aim of our study was to determine the frequency of CYP2D6 allelic variants and the prevalence of predicted CYP2D6 phenotypes in patients who were suffering from difficult-to-treat depression and compare the data with those for the healthy population of Hungary.55 patients who failed to respond to 2 or more adequate trials of different CYP2D6-dependent antidepressants were selected for genotyping.The prevalence of the predicted CYP2D6 phenotypes in the patient population was 1.8% for the UMs, 80.0% for EMs, 3.6% for IMs and 14.5% for PMs compared with 1.9% for UMs, 83.3% for EMs, 6.5% for IMs and 8.3% for PMs in the Hungarian population.The CYP2D6 allele frequencies and the predicted phenotype distributions in patients with difficult-to-treat depression were not significantly different to those found in the healthy population of Hungary. The cumulative frequency of the CYP2D6*1XN, *2XN and *35XN alleles was 0.9% in the patient population -suggesting that CYP2D6 duplication or multiplication does not play a significant role in antidepressant pharmacotherapy failure in this patient sample. The cumulative frequency of the non-functional alleles (33.5%) and the prevalence of the genetically determined PM phenotype (14.5%) were relatively high in the patient group. These figures draw attention to the possibility of unrecognised and non-reported side effects and non-adherence to drug treatment.
JPC - Journal of Planar Chromatography - Modern TLC, 2010
ABSTRACT Thin-layer chromatography with microbiological detection (direct bioautography) of ampho... more ABSTRACT Thin-layer chromatography with microbiological detection (direct bioautography) of amphotericin B has never been reported. The combination of these methods can be used advantageously, especially when not only chemical identification of samples is required, but also when antifungal activity is of interest. In this paper a fast and easy-to-perform method is introduced in which major (R(F) 0.46) and minor (R(F) 0.31) components can be separated from amphotericin B, which itself is not a homogenous substance but mixture of polyenes. Thin-layer chromatography is performed on silica gel layers with chloroform methanol borate buffer 4:5:1 (v/v) as optimized mobile phase, and the microbiological activity of amphotericin B can be measured sensitively by direct bioautography. Candida albicans (ATCC 90028) and Saccharomyces cerevisiae (ATCC 9763) fungus strains were tested. Among the detection methods investigated, direct bioautography with Candida albicans proved to be the most sensitive, with a detection limit of 0.8 ng per spot. For densitometric evaluation of plates with (385 nm) ten times more substance is required, and with a UV lamp (366 nm) as much as 50 ng AmB per spot is needed to visualize the main component.
A growing number of online pharmacies have been established worldwide. Among them are numerous il... more A growing number of online pharmacies have been established worldwide. Among them are numerous illegal websites selling medicine without valid medical prescriptions or distributing substandard or counterfeit drugs. Only a limited number of studies have been published on Internet pharmacies with regard to patient safety, professionalism, long-term follow-up, and pharmaceutical legitimacy verification. In this study, we selected, evaluated, and followed 136 Internet pharmacy websites aiming to identify indicators of professional online pharmacy service and online medication safety. An Internet search was performed by simulating the needs of potential customers of online pharmacies. A total of 136 Internet pharmacy websites were assessed and followed for four years. According to the LegitScript database, relevant characteristics such as longevity, time of continuous operation, geographical location, displayed contact information, prescription requirement, medical information exchange, and pharmaceutical legitimacy verification were recorded and evaluated. The number of active Internet pharmacy websites decreased; 23 of 136 (16.9%) online pharmacies ceased operating within 12 months and only 67 monitored websites (49.3%) were accessible at the end of the four-year observation period. However, not all operated continuously, as about one-fifth (31/136) of all observed online pharmacy websites were inaccessible provisionally. Thus, only 56 (41.2%) Internet-based pharmacies were continuously operational. Thirty-one of the 136 online pharmacies (22.8%) had not provided any contact details, while only 59 (43.4%) displayed all necessary contact information on the website. We found that the declared physical location claims did not correspond to the area of domain registration (according to IP address) for most websites. Although the majority (120/136, 88.2%) of the examined Internet pharmacies distributed various prescription-only medicines, only 9 (6.6%) requested prior medical prescriptions before purchase. Medical information exchange was generally ineffective as 52 sites (38.2%) did not require any medical information from patients. The product information about the medicines was generally (126/136, 92.6%) not displayed adequately, and the contents of the patient information leaflet were incomplete in most cases (104/136, 76.5%). Numerous online operators (60/136, 44.1%) were defined as rogue Internet pharmacies, but no legitimate Internet-based pharmacies were among them. One site (0.7%) was yet unverified, 23 (16.9%) were unapproved, while the remaining (52/136, 38.2%) websites were not available in the LegitScript database. Contrary to our prior assumptions, prescription or medical information requirement, or the indication of contact information on the website, does not seem to correlate with "rogue pharmacy" status using the LegitScript online pharmacy verification standards. Instead, long-term continuous operation strongly correlated (P<.001) with explicit illegal activity. Most Internet pharmacies in our study sample were illegal sites within the definition of "rogue" Internet pharmacy. These websites violate professional, legal, and ethical standards and endanger patient safety. This work shows evidence that online pharmacies that act illegally appear to have greater longevity than others, presumably because there is no compelling reason for frequent change in order to survive. We also found that one in five websites revived (closed down and reopened again within four years) and no-prescription sites with limited medicine and patient information are flourishing.
Chronic rhinosinusitis affects 1-4% of the adult population. The aetiology of this multifactorial... more Chronic rhinosinusitis affects 1-4% of the adult population. The aetiology of this multifactorial, chronic disease, which leads to a significant impairment of the quality of life, often accompanied by nasal polyposis, is not fully understood. In the past decade it was presumed that the disease, which causes characteristic eosinophilic infiltration of the nasal mucosa, is triggered by an enhanced (but not classical allergic IgE type) immune response. If this supposition is correct, then it appears obvious that the administration of amphotericin B nasal spray in adequate concentration following endoscopic polypectomy should be advantageous for these patients, and might even reduce the number of recurrent cases. To check on this assumption, the authors conducted a prospective randomized placebo-controlled trial involving 33 patients, 30 of whom remained in the study throughout. Patients with nasal polyposis were operated on with an endoscopic technique between 1 November 2005 and 1 October 2006; one group of them (group A, 14 randomly selected patients) was treated with a nasal spray containing 5 mg/ml amphotericin B, while the placebo group (group B, 16 randomly selected patients) received a nasal spray lacking amphotericin B. The results were evaluated with the aid of a modified Lund-Mackay CT score, the SNAQ-11 test (which evaluates changes in the symptoms), the life-quality test and endoscopy. The SPSS 14.0 for Windows program was utilized to process the data of examinations performed preoperatively and one year postoperatively. The CT scores of the group A patients exhibited wide scattering without signs of recovery one year after the operation. The CT scores of the group B patients indicated a slight improvement, though this did not prove significant in relation to group A. Both the SNAQ-11 test and the life-quality test revealed a significant improvement in each group, but the degrees of change in these tests did not significantly differ between the two groups of patients. The endoscopic findings indicated a slight improvement to the advantage of the amphotericin B-treated group 12 months after the operation. These results lead to the conclusion that the administration of amphotericin B nasal spray to patients operated on for nasal polyposis does not give rise to a significant alteration in CT scores, clinical symptoms, or quality of life. The more favourable clinical aspects observed in the amphotericin B-treated group during the endoscopic follow-up did not correspond to an improvement in the symptoms. In connection with the conclusions drawn from this study the authors discuss the available data on the fungal theory. They critically analyse the contradictory observations of 7 recent clinical studies.
As internet is now available to nearly everyone in Hungary, the accessibility of websites offerin... more As internet is now available to nearly everyone in Hungary, the accessibility of websites offering pharmaceutical products is also increasing. The national and international regulation of these sites is currently an unsolved problem worldwide, thus potentially harmful, counterfeit and prescription only medicines are easily accessible on the market. We aimed to measure and estimate the current situation of the ordering of online medicines. In 5 Hungarian cities 434 self-administered questionnaires were collected in community pharmacies. Our results show that 6.2% of the respondents have already ordered drugs or dietary supplements online and approximately same amount of people are considering this option in the near future. Based on our survey mostly the educated, the 30-49 year old people and women are likely to buy drugs online. Every fifth respondent reported willingness to buy drugs online from abroad if lower prices were offered. Most people do not know that the quality of medicines purchased online could be different from the ones purchased from community pharmacies. We would like to draw attention of healthcare professionals to the rising popularity and potential risks of drugs available online.
Amphotericin B can be determined by chemical (HPLC, spectrophotometry) and microbiological (bioas... more Amphotericin B can be determined by chemical (HPLC, spectrophotometry) and microbiological (bioassay) methods. The utilization of both during a stability test can give more detailed information about the activity and concentration change of amphotericin B solutions. Previously published HPLC methods do not lay stress on the separation of by-constituents present in the substance. We have also observed that the bioassay conditions described in the Ph. Eur. 6. are not suitable for the measurement of concentration change experienced during a stability test. The aim of our study was to optimize the chemical and microbiological methods. We have improved the eluent system based on earlier HPLC methods for the separation of the main heptaene and the minor tetraene by-constituents in Fungizone (Bristol-Myers Squibb). The most optimal bioassay conditions were determined where a relatively wide concentration range can be measured. With the improved methods both chemical and microbiological cha...
Recent studies have shown that the presence of fungal cells in the nasal mucosa may play an impor... more Recent studies have shown that the presence of fungal cells in the nasal mucosa may play an important role in the development of chronic rhinosinusitis with nasal polyps. In 2006 a pilot clinical trial was organized by the Department of Otorhinolaryngology, Head and Neck Surgery and the Pharmaceutical Institute of the Medical University of Pécs for the treatment of patients with chronic rhinosinusitis with nasal polyps. In our study we investigated the stability of the 5 mg/ml amphotericin B solutions (Fungizone) with chemical (spectrophotometry) and biological (bioassay) detection. The effect of storage temperature and the addition of 5% glucose was evaluated on the stability of the solutions for three months. The two detection methods showed different results. According to the chemical analysis the samples are considered relatively stable under all observed conditions (loss of concentration is: 14.2% at 20 degrees C and 4.5% at 4 degrees C). The bioassay shows complete loss of ant...
The increasing number of patients taking supplementary products together with prescribed medicine... more The increasing number of patients taking supplementary products together with prescribed medicines has become a new challenge for health care systems. These products may influence therapy outcomes by inducing unwanted effects. Particularly concerning is the potential for harmful interactions between prescribed medicines and supplementary products. The aims of the study were to evaluate supplement use, to identify and analyse potential interactions, and to assess the efficiency of computerised interaction screening. Participants of the study were inpatients and outpatients of a Hungarian university hospital. A cross-sectional point-of-care survey of 200 patients was carried out. Data was collected through personal interviews and a review of the medical records. Drug-drug, drug-supplement and supplement-supplement interactions were analysed with three interaction databases (Lexi-Interact Online, Medscape Drug Interaction Checker and Mediris). Prevalence of supplementary product use, number of medicines and supplementary products per patient, procurement sources of products, number of potentially severe interactions. There was a marked difference between data obtained from patient interviews and the medical records. 85.5 % of the surveyed patients took supplementary products during the 2 weeks prior to the interview. The average number of prescribed medicines and supplementary products were 7.8 and 2.5, respectively. Women were more likely to take supplements than men. There was no significant difference in supplement use between patients under or over 60 years, between inpatients and outpatients and among patients in various wards. 39.4 % of supplementary products were purchased outside a regulated pharmacy environment. Potentially severe drug-supplement interactions were detected with 45.2 % of supplement users; however the majority of interactions were not included in one or the other of the three databases. In addition to that the risk ratings of the same interactions varied greatly between databases. A significant number of patients are exposed to potential drug interactions with supplementary products; however interagreement among interaction databases is poor. Our data suggest that a full medication history should specifically address the intake of supplements.
The insufficient response of patients to antidepressant medications may result from several facto... more The insufficient response of patients to antidepressant medications may result from several factors, including altered drug metabolism. CYP2D6 genotyping may help assess the possible factors that contribute to difficult-to-treat depression. The aim of our study was to determine the frequency of CYP2D6 allelic variants and the prevalence of predicted CYP2D6 phenotypes in patients who were suffering from difficult-to-treat depression and compare the data with those for the healthy population of Hungary.55 patients who failed to respond to 2 or more adequate trials of different CYP2D6-dependent antidepressants were selected for genotyping.The prevalence of the predicted CYP2D6 phenotypes in the patient population was 1.8% for the UMs, 80.0% for EMs, 3.6% for IMs and 14.5% for PMs compared with 1.9% for UMs, 83.3% for EMs, 6.5% for IMs and 8.3% for PMs in the Hungarian population.The CYP2D6 allele frequencies and the predicted phenotype distributions in patients with difficult-to-treat depression were not significantly different to those found in the healthy population of Hungary. The cumulative frequency of the CYP2D6*1XN, *2XN and *35XN alleles was 0.9% in the patient population -suggesting that CYP2D6 duplication or multiplication does not play a significant role in antidepressant pharmacotherapy failure in this patient sample. The cumulative frequency of the non-functional alleles (33.5%) and the prevalence of the genetically determined PM phenotype (14.5%) were relatively high in the patient group. These figures draw attention to the possibility of unrecognised and non-reported side effects and non-adherence to drug treatment.
JPC - Journal of Planar Chromatography - Modern TLC, 2010
ABSTRACT Thin-layer chromatography with microbiological detection (direct bioautography) of ampho... more ABSTRACT Thin-layer chromatography with microbiological detection (direct bioautography) of amphotericin B has never been reported. The combination of these methods can be used advantageously, especially when not only chemical identification of samples is required, but also when antifungal activity is of interest. In this paper a fast and easy-to-perform method is introduced in which major (R(F) 0.46) and minor (R(F) 0.31) components can be separated from amphotericin B, which itself is not a homogenous substance but mixture of polyenes. Thin-layer chromatography is performed on silica gel layers with chloroform methanol borate buffer 4:5:1 (v/v) as optimized mobile phase, and the microbiological activity of amphotericin B can be measured sensitively by direct bioautography. Candida albicans (ATCC 90028) and Saccharomyces cerevisiae (ATCC 9763) fungus strains were tested. Among the detection methods investigated, direct bioautography with Candida albicans proved to be the most sensitive, with a detection limit of 0.8 ng per spot. For densitometric evaluation of plates with (385 nm) ten times more substance is required, and with a UV lamp (366 nm) as much as 50 ng AmB per spot is needed to visualize the main component.
A growing number of online pharmacies have been established worldwide. Among them are numerous il... more A growing number of online pharmacies have been established worldwide. Among them are numerous illegal websites selling medicine without valid medical prescriptions or distributing substandard or counterfeit drugs. Only a limited number of studies have been published on Internet pharmacies with regard to patient safety, professionalism, long-term follow-up, and pharmaceutical legitimacy verification. In this study, we selected, evaluated, and followed 136 Internet pharmacy websites aiming to identify indicators of professional online pharmacy service and online medication safety. An Internet search was performed by simulating the needs of potential customers of online pharmacies. A total of 136 Internet pharmacy websites were assessed and followed for four years. According to the LegitScript database, relevant characteristics such as longevity, time of continuous operation, geographical location, displayed contact information, prescription requirement, medical information exchange, and pharmaceutical legitimacy verification were recorded and evaluated. The number of active Internet pharmacy websites decreased; 23 of 136 (16.9%) online pharmacies ceased operating within 12 months and only 67 monitored websites (49.3%) were accessible at the end of the four-year observation period. However, not all operated continuously, as about one-fifth (31/136) of all observed online pharmacy websites were inaccessible provisionally. Thus, only 56 (41.2%) Internet-based pharmacies were continuously operational. Thirty-one of the 136 online pharmacies (22.8%) had not provided any contact details, while only 59 (43.4%) displayed all necessary contact information on the website. We found that the declared physical location claims did not correspond to the area of domain registration (according to IP address) for most websites. Although the majority (120/136, 88.2%) of the examined Internet pharmacies distributed various prescription-only medicines, only 9 (6.6%) requested prior medical prescriptions before purchase. Medical information exchange was generally ineffective as 52 sites (38.2%) did not require any medical information from patients. The product information about the medicines was generally (126/136, 92.6%) not displayed adequately, and the contents of the patient information leaflet were incomplete in most cases (104/136, 76.5%). Numerous online operators (60/136, 44.1%) were defined as rogue Internet pharmacies, but no legitimate Internet-based pharmacies were among them. One site (0.7%) was yet unverified, 23 (16.9%) were unapproved, while the remaining (52/136, 38.2%) websites were not available in the LegitScript database. Contrary to our prior assumptions, prescription or medical information requirement, or the indication of contact information on the website, does not seem to correlate with "rogue pharmacy" status using the LegitScript online pharmacy verification standards. Instead, long-term continuous operation strongly correlated (P<.001) with explicit illegal activity. Most Internet pharmacies in our study sample were illegal sites within the definition of "rogue" Internet pharmacy. These websites violate professional, legal, and ethical standards and endanger patient safety. This work shows evidence that online pharmacies that act illegally appear to have greater longevity than others, presumably because there is no compelling reason for frequent change in order to survive. We also found that one in five websites revived (closed down and reopened again within four years) and no-prescription sites with limited medicine and patient information are flourishing.
Chronic rhinosinusitis affects 1-4% of the adult population. The aetiology of this multifactorial... more Chronic rhinosinusitis affects 1-4% of the adult population. The aetiology of this multifactorial, chronic disease, which leads to a significant impairment of the quality of life, often accompanied by nasal polyposis, is not fully understood. In the past decade it was presumed that the disease, which causes characteristic eosinophilic infiltration of the nasal mucosa, is triggered by an enhanced (but not classical allergic IgE type) immune response. If this supposition is correct, then it appears obvious that the administration of amphotericin B nasal spray in adequate concentration following endoscopic polypectomy should be advantageous for these patients, and might even reduce the number of recurrent cases. To check on this assumption, the authors conducted a prospective randomized placebo-controlled trial involving 33 patients, 30 of whom remained in the study throughout. Patients with nasal polyposis were operated on with an endoscopic technique between 1 November 2005 and 1 October 2006; one group of them (group A, 14 randomly selected patients) was treated with a nasal spray containing 5 mg/ml amphotericin B, while the placebo group (group B, 16 randomly selected patients) received a nasal spray lacking amphotericin B. The results were evaluated with the aid of a modified Lund-Mackay CT score, the SNAQ-11 test (which evaluates changes in the symptoms), the life-quality test and endoscopy. The SPSS 14.0 for Windows program was utilized to process the data of examinations performed preoperatively and one year postoperatively. The CT scores of the group A patients exhibited wide scattering without signs of recovery one year after the operation. The CT scores of the group B patients indicated a slight improvement, though this did not prove significant in relation to group A. Both the SNAQ-11 test and the life-quality test revealed a significant improvement in each group, but the degrees of change in these tests did not significantly differ between the two groups of patients. The endoscopic findings indicated a slight improvement to the advantage of the amphotericin B-treated group 12 months after the operation. These results lead to the conclusion that the administration of amphotericin B nasal spray to patients operated on for nasal polyposis does not give rise to a significant alteration in CT scores, clinical symptoms, or quality of life. The more favourable clinical aspects observed in the amphotericin B-treated group during the endoscopic follow-up did not correspond to an improvement in the symptoms. In connection with the conclusions drawn from this study the authors discuss the available data on the fungal theory. They critically analyse the contradictory observations of 7 recent clinical studies.
As internet is now available to nearly everyone in Hungary, the accessibility of websites offerin... more As internet is now available to nearly everyone in Hungary, the accessibility of websites offering pharmaceutical products is also increasing. The national and international regulation of these sites is currently an unsolved problem worldwide, thus potentially harmful, counterfeit and prescription only medicines are easily accessible on the market. We aimed to measure and estimate the current situation of the ordering of online medicines. In 5 Hungarian cities 434 self-administered questionnaires were collected in community pharmacies. Our results show that 6.2% of the respondents have already ordered drugs or dietary supplements online and approximately same amount of people are considering this option in the near future. Based on our survey mostly the educated, the 30-49 year old people and women are likely to buy drugs online. Every fifth respondent reported willingness to buy drugs online from abroad if lower prices were offered. Most people do not know that the quality of medicines purchased online could be different from the ones purchased from community pharmacies. We would like to draw attention of healthcare professionals to the rising popularity and potential risks of drugs available online.
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