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Biomedical subjects

A C Egberts

Publications and source records attributed to A C Egberts.

At least 19 recordsLinked to original sources
PubMed2005

Reasons for switching between antipsychotics in daily clinical practice.

BACKGROUND: Previous research that atypical antipsychotics were switched less often compared to typical antipsychotics, suggesting overall better treatment satisfaction. The objective of this study was to investigate the reasons for switching antipsychotics after initiating oral treatment with either typical or atypical antipsychotics in a clinical setting. PATIENTS AND METHODS: A total of 123 patients that switched antipsychotic therapy were recruited from 17 psychiatric hospitals, of which 46 % switched because of lack of effect and 45 % because of adverse effects. RESULTS: No significant differences were found between users of atypical versus typical antipsychotics in reasons for switching, both for overall adverse events, and lack of effect. In users of atypical antipsychotics extrapyramidal effects were reported less often as reason for switching (adjusted OR = 0.18 (95 % CI = (0.07 - 0.51)). Patients on atypical antipsychotics switched more often because of weight gain (adjusted OR = 12.8 (95 % CI = (1.50 - 109)). CONCLUSION: In conclusion, when switching occurred, no difference was found in the frequency of general tolerability or reported lack of effectiveness. However, the type of adverse event as a reason for switching differed between atypical and typical antipsychotics.

Adolescent↗
PubMed2004

Reduction in the therapeutic intensity of abortive migraine drug use during ACE inhibition therapy--a pilot study.

INTRODUCTION: Since a few case reports have demonstrated some beneficial effects of angiotensin converting enzyme (ACE) inhibitors in migraine prevention, we were interested in studying the impact of ACE inhibitors and angiotensin II receptor antagonists (Ang II) on the consumption of specific abortive migraine drugs and, therefore, indirectly on the frequency of migraine attacks. METHODS: Data from a large prescription database involving 95 patients initiating a specific abortive migraine drug (ergotamine or a triptan) and subsequently treated with either an ACE inhibitor or angiotensin receptor antagonist (index group: ACE/Ang II) or diuretic (reference group) were analysed. The effects of ACE/Ang II inhibition as well as diuretic therapy on reducing the frequency of migraine attacks were assessed by measuring the mean consumption of abortive migraine drug use, in DDDs per month ('therapeutic intensity'), before, during and after ACE/Ang II or diuretic therapy. A 'therapeutic fluctuation intensity estimate' of abortive migraine drug use for all patients was likewise calculated. RESULTS: On an individual level, the therapeutic intensity (TI) fluctuation estimate, 'during' relative to 'before' ACE diuretic therapy, was significantly larger for the ACE/Ang II group (62% reduction) than for the diuretic group (24% reduction) (p = 0.02). For patients who continued abortive migraine drug use during and after ACE/Ang II or diuretic therapy, a significantly larger reduction in this estimate was observed during ACE/Ang II inhibition (68.9%) compared to during diuretic therapy (10.5% increase) (p = 0.004). The TI fluctuation estimate, after relative to 'during', had increased by 50.3% after ACE/Ang II inhibition and had reduced by 22.2% after diuretic treatment (p = 0.1). CONCLUSIONS: A clear reduction in the TI of abortive migraine drug use during the use of ACE inhibitors as compared to diuretic treatment was observed. Our findings may indirectly support a positive effect of ACE/Ang II inhibition on the frequency and severity of migraine attacks, as observed in other studies and reports.

Adolescent↗
PubMed2003

[Withdrawal symptoms in a neonate following exposure to venlafaxine during pregnancy].

Withdrawal symptoms occurred in a male neonate after maternal use of venlafaxine for depression during pregnancy. The symptoms were restlessness, hypertonia, jitteriness, irritability and poor feeding. The diagnosis was confirmed by a temporary improvement after administration of a low dose (1 mg) of venlafaxine to the boy. Eventually the symptoms began to decline spontaneously, and ceased after 8 days. Exposure to venlafaxine and other antidepressants which inhibit serotonin reuptake during the third trimester of pregnancy carries the risk of a neonatal withdrawal syndrome.

Antidepressive Agents, Second-Generation↗
PubMed2001

Assessment of indicators for hospital drug formulary non-adherence.

BACKGROUND: Translation of rational drug therapy into practice remains an international problem. Although pharmacotherapeutic treatment guidelines (PTGs) as managerial tools are favoured over hospital drug formularies (HDFs), the latter are still applied in most hospitals. HDF enforcement often leads to time-consuming consultation from the perspective of both pharmacy staff and prescriber. So far, research on HDFs has only been conducted outside Europe. Moreover, this research has only been descriptive. Straightforward indicators qualitatively characterising HDF non-adherence have never been assessed. METHODS: A retrospective 1:1 case-control study was conducted across three general teaching hospitals. Non-HDF requests were compared with HDF requests. Data were multivariably analysed, considering patient, prescriber, drug, and HDF characteristics as possible indicators for non-adherence. RESULTS: HDF adherence was almost universal across characteristics. Non-adherence was characterised by newly marketed drugs, drugs that were part of patients' pre-admission drug therapy, drugs with many fellow drugs within the drug group on the market, and drugs originating from a drug group for which the HDF was highly restrictive. Contrary to common perception, non-adherence was independent of medical specialty, therapeutic area, and patient characteristics. CONCLUSION: This research provides an epidemiological framework for hospitals (drug and therapeutics committees) for evaluating pharmacy data on HDF non-adherence. It can be used for educational tailor-made feedback to prescribers and for drug selection when the inclusion of newly marketed drugs is considered or HDF restrictiveness for certain drug groups is reconsidered. Moreover, it demonstrates the importance of a regional approach involving secondary and primary health care to establish continuity in seamless care of drug therapy.

Data Collection↗
PubMed2001

Nature, frequency and determinants of prescription modifications in Dutch community pharmacies.

AIMS: To examine the nature, frequency and determinants of prescription modifications in Dutch community pharmacies. METHODS: A prospective case-control study comparing modified prescriptions with nonmodified prescriptions was carried out in 141 Dutch community pharmacies. 2014 modified prescriptions (cases), collected in the selected pharmacies on a predetermined day in a specific period (25th February until 12th March 1999) and 2581 nonmodified prescriptions (controls) randomly selected on the same day were studied. The nature and frequency of prescription modifications and patient, drug and prescriber related determinants for a modified prescription were assessed. RESULTS: The overall incidence of prescription modifications was 4.3%, with a mean of 14.3 modifications per pharmacy per day. For prescription only medicines (POM) the incidence was 4.9%. The majority of POM modifications concerned a clarification (71.8%). In 22.2% a prescription could potentially have had clinical consequences when not altered; in more than half of the latter it concerned a dose error (13.7% of all cases). POM prescriptions of patients of 40-65 years had a significantly lower chance of modification compared with those of younger people (OR = 0.74 [0.64-0.86]). With respect to medication-class, we found a higher chance of POM modifications in the respiratory domain (OR = 1.48 [1.23-1.79]) and a decreased chance for nervous system POMs (OR = 0.71 [0.61-0.83]). With regard to prescriber-related determinants modifications were found three times more often in non printed prescriptions than in printed ones (OR = 3.30 [2.90-3.75]). Compared with prescriptions by the patient's own GP, prescriptions of specialists (OR = 1.82 [1.57-2.11]), other GP's (OR = 1.49 [1.02-2.17]) and other prescribers such as dentists and midwives (OR = 1.95 [1.06-3.57]) gave a higher probability of prescription modifications. When a GP had no on-line access to the computer of the pharmacy the chance of a modification was also higher (OR = 1.61 [1.33-1.94]). Multivariate analysis revealed that a nonprinted prescription was the strongest independent determinant of prescription modifications (OR = 3.32 [2.87-3.84]), remaining so after adjustment for GP computer link to the pharmacy and for type of prescriber. CONCLUSIONS: At least 30% of Dutch community pharmacies corrected 2.8 POM prescriptions per pharmacy per working day, which could potentially have had clinical consequences if not altered. If the study sample is representative for The Netherlands, Dutch community pharmacies correct a total of approximately 4400 of these prescriptions per working day. Using computerized systems to generate prescriptions is an important strategy to reduce the incidence of prescription errors.

Adult↗
PubMed2001

Determinants of signal selection in a spontaneous reporting system for adverse drug reactions.

AIMS: Detection of new adverse drug reactions (ADR) after marketing is often based on a manual review of reports sent to a Spontaneous Reporting System (SRS). Among the many potential signals that are identified, only a limited number are important enough to require further attention. The goal of this study is to gain insight into factors contributing to the selection and dissemination of possible signals originating from the SRS maintained by the Netherlands Pharmacovigilance Foundation. METHODS: In a case control design, all signals (n = 42) disseminated to the Medicines Evaluation Board from the second quarter of 1997 until the third quarter of 2000, which could be expressed as a combination of a single ATC code and a single WHO preferred term, were included. For each case, four controls were matched in time. Logistic regression analysis was used to investigate the influence of various factors, such as the fact whether the ADR or drug is new, the strength of the association, the seriousness of the reaction and the documentation of the reports. RESULTS: Multivariate analysis showed that the presence of a 'serious report' (Odds Ratio 3.8, 95% CI 1.3, 11.0), a WHO 'critical term' (OR 4.7, 95% CI 1.8, 13), the ADR being unlabelled (OR 6.1, 95% CI 2.3, 16) and the presence of a disproportionate association (OR 3.5, 95% CI 1.4, 8) were all independently associated with signal selection. The number of reports and the time after marketing of the drug had no influence. CONCLUSIONS: This study showed that selection of signals is based on both qualitative and quantitative aspects. Knowledge of these factors may improve the efficiency of the underlying signal selection process.

Adverse Drug Reaction Reporting Systems↗
PubMed2001

The Dutch cohort of sildenafil users: baseline characteristics.

OBJECTIVE: To identify a Dutch cohort of sildenafil users and describe their baseline characteristics. PATIENTS AND METHODS: Each pharmacy in The Netherlands (n = 1571) was asked to identify prospectively the first 20 sildenafil prescriptions in their pharmacy over 1 year, and to complete and return a registration form. The collected data included patient characteristics, the details of the sildenafil prescription (date, prescriber, number of prescriptions, dosing), and the use of co-medication by the patient in the year preceding the sildenafil prescription. RESULTS: Data were collected from 4460 sildenafil prescriptions during the year under study, relating to 3477 individual patients. Most of the cohort had cardiovascular morbidity or diabetes. Sildenafil seems to have been used by a new, previously untreated population of patients with erectile dysfunction. In addition, 69 men were identified who could have been using nitrates and sildenafil concomitantly. CONCLUSION: A cohort of patients using sildenafil was identified and characterized; they appeared to be representative of sildenafil users in The Netherlands. This cohort will be followed prospectively to evaluate the medical status (particularly cardiovascular) of the patients with time.

Adult↗
PubMed2001

Patterns of ergotamine and sumatriptan use in the Netherlands from 1991 to 1997.

The objective of this study was to assess usage patterns of ergotamine and sumatriptan over a period of 6 years, primarily to evaluate the impact that sumatriptan has had on the prescription of ergotamine. This study used ergotamine and sumatriptan prescription data representing inhabitants of eight cities in the Netherlands and covering the period of 1991-1997. The yearly incidence of new users between 1991 and 1997 was estimated for both drugs as well as for the drug of first choice to be prescribed to patients initiating specific abortive migraine treatment with either ergotamine or sumatriptan. Intra-individual ergotamine and sumatriptan usage patterns, characterized by single (incidental), continuous (rate of retention) or switch use, were examined for five patient cohorts, each for a follow-up period of 1 year. During the year of sumatriptan introduction (1991-1992), the overall incidence of new use for both drugs was highest (5.4 per 1000 inhabitants). Hereafter, a substantial reduction of more than 50% was observed. From 1992 to 1996, the yearly incidence of ergotamine first-time use was significantly higher than that of sumatriptan and up to 1996 ergotamine was more than twice as likely than sumatriptan to be prescribed to patients initiating specific abortive treatment. Hereafter, sumatriptan was as likely as ergotamine to be prescribed as the drug of first choice, which coincided with the full reimbursement of sumatriptan tablets. Overall, neurologists were more likely than general practitioners (GPs), to prescribe sumatriptan as the drug of first choice. Approximately half of the total study population were identified as single-time users. This phenomonen occurred more frequently in the ergotamine cohorts. The sumatriptan cohorts displayed a slight yet significant stronger retention rate compared with the ergotamine cohorts. The overall impact of sumatriptan on ergotamine use in The Netherlands was marginal, predominantly due to GP's adherence to migraine treatment guidelines and reimbursement policies concerning sumatriptan tablets. Overall, incidental use was relatively high and may reflect the reported difficulties in diagnosing migraine, lack of patient-doctor consultation, or that anticipated benefits of the drug were not achieved. Further study is required to clarify these issues.

Adolescent↗
PubMed2001

Reduction in the intensity of abortive migraine drug use during coumarin therapy.

OBJECTIVE: To investigate the impact of coumarin therapy on migraine attack frequency. BACKGROUND: Sporadic case reports and clinical studies have described beneficial effects of coumarin therapy on migraine severity. DESIGN AND METHODS: A retrospective follow-up study based on a prescription database covering a population of 450 000 was conducted. All patients using an abortive migraine drug (ergotamine or sumatriptan) and subsequently treated with either coumarin (index group) or low-dose acetylsalicylic acid (control group) were analyzed. The impact of coumarin and low-dose acetylsalicylic acid on the frequency of migraine attacks was assessed by measuring the intensity of ergotamine and sumatriptan use, in defined daily doses per month per patient, before and during coumarin or acetylsalicylic acid treatment. In addition, a "therapeutic intensity reduction" was determined for each patient. RESULTS: The study population consisted of 92 patients; 35% had been prescribed coumarin and 65% had been prescribed low-dose acetylsalicylic acid after the initiation of ergotamine or sumatriptan. Two thirds of the study population was treated with ergotamine. Overall, ergotamine and sumatriptan use for the coumarin cohort decreased from 6.4 defined daily doses per month prior to coumarin treatment to 3.0 defined daily doses during coumarin treatment, compared with a reduction from 5.2 defined daily doses per month to 4.4 defined daily doses per month for the low-dose acetylsalicylic acid cohort (P>.05). The therapeutic intensity of ergotamine and sumatriptan use was significantly decreased by 40% for the coumarin cohort, compared with 4.7% for the low-dose acetylsalicylic acid cohort (P=.004). CONCLUSIONS: We observed that coumarin treatment was clearly associated with a reduction in the therapeutic intensity of abortive migraine drug use in comparison with low-dose aspirin treatment. This suggests that, overall, the coumarin cohort had experienced a substantial reduction in the frequency of migraine attacks during anticoagulation treatment. Our findings, as well as those of others, justify a controlled clinical trial to further establish the effects of coumarin therapy on migraine severity and its possible role in the prophylactic management of patients suffering from migraine.

Anticoagulants↗
PubMed2000

Cyclical etidronate use is not associated with symptoms of peptic ulcer disease.

OBJECTIVE: To investigate whether the alkylbisphosphonate etidronate is associated with an increased risk of gastrointestinal symptoms. METHODS: We conducted an observational follow-up study on a possible relationship between etidronate use and the risk of gastrointestinal symptoms in a cohort of 2754 women over 50 years of age. The study was performed with data on drug prescriptions obtained from the PHARMO database in the Netherlands. Women were included when they used either cyclical etidronate (n = 1050) or estrogen (n = 1704) for at least 14 days. They were followed-up for incident use of antiulcer drugs while on exposure medication. RESULTS: The mean ages were 72 years and 59 years in the etidronate and estrogen groups, respectively. In total, there were 95 women with incident prescriptions for gastrointestinal events after a median duration of follow-up of 2.7 months (range 0.1-19.4 months). The crude relative risk of a gastrointestinal event for etidronate compared with estrogen use was 1.2 [95% confidence interval (95% CI) 0.8-1.8]. Adjusted for baseline age, use of corticosteroids, salicylates and nonsteroidal anti-inflammatory drugs, the relative risk reversed to 0.6 (95% CI 0.4-1.2). CONCLUSION: The use of cyclical etidronate is not associated with an elevated risk of symptoms of peptic ulcer disease.

Aged↗
PubMed2000

Detecting drug-drug interactions using a database for spontaneous adverse drug reactions: an example with diuretics and non-steroidal anti-inflammatory drugs.

OBJECTIVE: Drug-drug interactions are relatively rarely reported to spontaneous reporting systems (SRSs) for adverse drug reactions. For this reason, the traditional approach for analysing SRS has major limitations for the detection of drug-drug interactions. We developed a method that may enable signalling of these possible interactions, which are often not explicitly reported, utilising reports of adverse drug reactions in data sets of SRS. As an example, the influence of concomitant use of diuretics and non-steroidal anti-inflammatory drugs (NSAIDs) on symptoms indicating a decreased efficacy of diuretics was examined using reports received by the Netherlands Pharmacovigilance Foundation Lareb. METHODS: Reports received between 1 January 1990 and 1 January 1999 of patients older than 50 years were included in the study. Cases were defined as reports with symptoms indicating a decreased efficacy of diuretics, non-cases as all other reports. Exposure categories were the use of NSAIDs or diuretics versus the use of neither of these drugs. The influence of the combined use of both drugs was examined using logistic regression analysis. RESULTS: The odds ratio of the statistical interaction term of the combined use of both drugs was increased [adjusted odds ratio 2.0, 95% confidence interval (CI) 1.1-3.7], which may indicate an enhanced effect of concomitant drug use. CONCLUSION: The findings illustrate that spontaneous reporting systems have a potential for signal detection and the analysis of possible drug-drug interactions. The method described may enable a more active approach in the detection of drug-drug interactions after marketing.

Adverse Drug Reaction Reporting Systems↗
PubMed2000

Risk factors for the development of adverse drug events in hospitalized patients.

Adverse drug events in hospitalized patients lead to increased morbidity, mortality and costs. Early detection of adverse drug events could aid in the prevention of these adverse outcomes. A cost-effective system for the early detection of adverse drug events should focus on high risk patients. A study was set up with the primary aim to identify characteristics that are associated with the development of adverse drug events (ADEs) in hospitalized patients. ADE reports were gathered from physicians and nurses (spontaneous reports) and from patients after intensive ward interviews by hospital pharmacists. All patients admitted to the internal medicine wards of two Dutch hospitals, during a two month period, were included. The following characteristics were analyzed for their potential relationship to the occurrence of ADEs: age (categorized), gender, number of drugs prescribed during hospital stay, types of drugs used and changes in drug use on admission. Age was found to be inversely associated with the development of ADEs (OR 0.36, CI 0.21-0.61 for age category > 80 years; OR 0.56; CI 0.31-1.02 for age category 75-80 years and OR 0.69; CI 0.42-1.11 for age category 60-74 years). Furthermore, statistically significant associations were found for the number of drugs prescribed per hospitalized patient (for the class of 4-6 drugs per patient OR 2.61, CI 1.32-5.18), for newly prescribed drugs (OR 6.65, CI 2.63-16.81) and for the cessation of drugs on hospital admission (OR 1.50, CI 1.02-2.20). The use of gastrointestinal drugs (OR 2.13, CI 1.32-3.45), central nervous system drugs (OR 1.66, CI 1.07-2.57) and antibiotics (OR 2.44, CI 1.65-3.60) were associated with the development of ADEs, when compared to all other drugs taken by the patients. In this study, the most important risk factors are the number of drugs used per patient and the starting of a new drug during hospitalization. As most hospitalized patients start new drug therapies while in hospital, this seems an inappropriate focus. However, careful monitoring of patients using more than 7 drugs at a time may be possible in a cost-effective system for the early detection of ADEs.

Adult↗
PubMed2000

Stabilization of oral anticoagulant therapy in hospitalized patients and characteristics associated with lack of stabilization.

The initiation and stabilization of oral anticoagulant therapy in hospitalized patients in a setting without specialized medical or pharmaceutical advice, was studied. In addition, potential risk factors for lack of stabilization were studied. All patients from three wards (orthopaedic surgery, general surgery and internal medicine) in two Dutch hospitals, who were started on oral anticoagulant therapy and who gave informed consent, were included in this three months prospective follow-up study. When a patient had two consecutive INR's within the range 2-3 during hospitalization (on day 6 or later), he was defined as stable. Stable and unstable patients were compared with respect to age, gender, quetelet index, length of hospital stay, indication for oral anticoagulant therapy, induction dosing schedule of oral anticoagulant therapy, prescribing physician, type of hospital (teaching or non-teaching), concurrently used drugs, concurrently used drugs known to potentially interact with oral anticoagulant therapy (drug-drug interactions that influence INR) and (co)morbidity. A total of 125 patients, who all used acenocoumarol as oral anticoagulant, were recruited in the study. The study population mainly comprised orthopaedic discharges on prophylactic oral anticoagulants. The mean length of hospital stay was 14.5 days (median 11.0, standard deviation (SD) 10.2) for the patients included in the study (patients with a short length of stay < 6 days were excluded from the study, because of the definition of stability). 43 patients (34%) became stable during hospitalization. The second INR within the range was reached after on average 11.1 days (median 10.0, SD 4.5). 18 different induction dosing schedules were used. Differences in apparent risk of INR instability were statistically associated with length of hospital stay (odds ratio (OR) 0.85, 95% confidence interval (CI) 0.78-0.92), concurrent use of musculoskeletal drugs, mainly NSAIDs, (OR 1.68, 95% CI 1.04-2.72) and two individual prescribing physicians (OR 6.61, 95% CI 1.47-29.82 for one physician and OR 0.23, 95% CI 0.06-0.99 for the other physician). This population has a high percentage of instability and reaches stability relatively late. The instability was associated with length of hospital stay, the concurrent use of musculoskeletal drugs (mostly NSAID's) and physician. Most of the unstable patients had INR's below therapeutic range, suggesting a conservative dosing habit. Part of the instability may also be due to the many different physicians who dose their own patients. Interventions to improve dosing may aid in better stabilization in hospitalized patients and thus in reduced length of hospital stay.

Administration, Oral↗
PubMed2000

Automated extraction of 11-nor-delta9-tetrahydrocannabinol carboxylic acid from urine samples using the ASPEC XL solid-phase extraction system.

The analysis of 11-nor-delta9-tetrahydrocannabinol-carboxylic acid (THCCOOH, the major metabolite of cannabis) in urine with gas chromatography and mass spectrometry (GC-MS) and solid-phase extraction (SPE) sample preparation is well documented. Automated SPE sample preparation of THCCOOH in urine, although potentially advantageous, is to our knowledge poorly investigated. The objective of the present study was to develop and validate an automated SPE sample-preparation step using ASPEC XL suited for GC-MS confirmation analysis of THCCOOH in urine drug control. The recoveries showed that it was not possible to transfer the protocol for the manual SPE procedure with the vacuum manifold to the ASPEC XL without loss of recovery. Making the sample more lipophilic by adding 1 mL 2-propanol after hydrolysis to the urine sample in order to overcome the problem of surface adsorption of THCCOOH led to an extraction efficiency (77%) comparable to that reached with the vacuum manifold (84%). The reproducibility of the automated SPE procedure was better (coefficient of variation 5%) than that of the manual procedure (coefficient of variation 12%). The limit of detection was 1 ng/mL, and the limit of quantitation was 4 ng/mL. Precision at the 12.5-ng/mL level was as follows: mean, 12.4 and coefficient of variation, 3.0%. Potential carryover was evaluated, but a carryover effect could not be detected. It was concluded that the proposed method is suited for GC-MS confirmation urinalysis of THCCOOH for prisons and detoxification centers.

Dronabinol↗
PubMed2000

Selective prescribing of spasmolytics.

BACKGROUND: Daily clinical practice often differs largely from the clinical trial setting, so extrapolation of outcomes from trial data, such as safety, effectiveness, and economic outcomes, can be deceptive. Prescribers may intend to treat a selected group of patients with new drugs; this practice could result in significant bias in assessing outcomes of these agents during their use in daily clinical practice. OBJECTIVE: To evaluate what type of patient received tolterodine compared with the spasmolytic drugs previously marketed (oxybutynin, flavoxate, emepronium). DESIGN: An observational, follow-up study. SETTING: Eighteen collaborating community pharmacies. PATIENTS: Aged > or = 18 years, noninstitutionalized; initial therapy with tolterodine, oxybutynin, flavoxate, or emepronium. RESULTS: Tolterodine was often used as a second-line and even as a third-line treatment, and was prescribed to a "polluted" population in terms of concomitant psychotropic medication. Tolterodine users were 7.5 times more likely to have received another spasmolytic drug (RR 7.5, 95% CI 4.8 to 11.9). In addition, these patients more frequently used antiparkinsonian drugs (RR 4.1, 95% CI 1.6 to 10.4) as well as antipsychotic drugs (RR 2.9, 95% CI 1.4 to 6.2). There was a small difference in concomitant use of antidepressants and benzodiazepines between patients receiving tolterodine versus those taking other spasmolytic drugs. CONCLUSIONS: Tolterodine is prescribed for a population differing from that receiving previously marketed spasmolytic drugs. Selective prescribing should recognized when evaluating new drugs in daily clinical practice. Policy makers, such as pharmacy and therapeutics committees, should consider this aspect in their formulary decisions since selective prescribing can lead to unjustified conclusions about a drug's therapeutic effects (e.g., efficacy, safety, cost-effectiveness).

Aged↗
PubMed2000

An ABC of drug-related problems.

The problems relating to the use of medicines are manifold. They may differ in pharmacological, pathological, epidemiological and legal respects, and may have different consequences, for example, as regards scientific study, regulation or rational use. Pharmacovigilance is concerned with all such problems: adverse effects and interactions as well as problems relating to ineffectiveness, inappropriate use, counterfeiting, dependence or poisoning. Practically all medicine-related problems can be classified in one basic system, taking into account their characteristics and distinctions. This system distinguishes between appropriate and inappropriate drug use; dose-related and dose-unrelated problems [corrected]; and types A ('drug actions'), B ('patient reactions') and C ('statistical') adverse effects. This classification may serve as an educational tool and may be useful in when choosing a study method and for the design of effective strategies in pharmacovigilance.

Drug Interactions↗
PubMed1999

[Clinical researchers and pharmaceutical industry. The examples of troglitazone and mibefradil].

A newly introduced drug may find many obstacles in its path. The intensity of marketing of new drugs can have unwanted effects. When new drugs are prescribed for a population that differs widely from that in clinical trials, unforeseen side effects can occur. The examples of troglitazone and mibefradil illustrate these mechanisms. It is the responsibility of the drug manufacturers and prescribers to let new drugs gradually find their therapeutic position. Otherwise exaggeration of untoward effects may lead to the speedy and possibly premature withdrawal of the drugs.

Antihypertensive Agents↗