R Afshari

Publications of R Afshari

• Metal mercury poisoning in two boys initially treated for brucellosis in Mashhad, Iran.

  Authors: M S Sasan, N Hadavi, R Afshari, S R Mousavi, A Alizadeh, M Balali-Mood

  Human & experimental toxicology. 08/2011;

  Elemental mercury (Hg) is the only metal which evaporates in room temperature and its inhalation may cause toxicity. Hg poisoning may occur by mishandling the metal, particularly in children who playElemental mercury (Hg) is the only metal which evaporates in room temperature and its inhalation may cause toxicity. Hg poisoning may occur by mishandling the metal, particularly in children who play with it. Wide-spectrum of the clinical presentations of chronic Hg poisoning may cause misdiagnosis, particularly when history of exposure is unknown. We report two cases of accidental Hg poisoning, which initially had been diagnosed and treated for brucellosis. The patients were two brothers (7 and 14 years old) who presented with pain in their lower extremities, sweating, salivation, weight loss, anorexia and mood changes on admission. Meticulous history taking revealed that they had played with a ball of Hg since 3 months before admission. The level of urinary Hg was 125.9 and 54.2 9 g/L in the younger and older brother, respectively (normal ≤25 g/L). The patients were successfully treated by dimercaprol and discharged in good condition 24 days after admission. These cases are being reported to emphasize the importance of acrodynia as a differential diagnosis for brucellosis in endemic areas.

• Population-based severity, onset and type of drug-drug interactions in prescriptions.

  Authors: E Taheri, R Afshari, L Nazemian

  Methods and findings in experimental and clinical pharmacology. 05/2010; 32(4):237-42.

  Inappropriate drug combinations occur frequently and may lead to serious adverse events. In Iran, drug overdose and interactions are relatively common but rarely reported and are mainly derived fromInappropriate drug combinations occur frequently and may lead to serious adverse events. In Iran, drug overdose and interactions are relatively common but rarely reported and are mainly derived from admitted subjects. The aim of this study was to determine the prevalence of possible drug-drug interactions via a population database survey in Mashhad, Iran. In this survey all prescriptions paid by insurance companies in the period 21rst March 2006 to 20th March 2008 were studied retrospectively. Data were gathered from the Division of Rational Use Drug, Food and Drug Vice Chancellor of Mashhad University of Medical Sciences, Iran. Drug interactions were categorized based on severity, onset and dynamic/kinetic nature. Incidence was calculated based on the number of interactions/1000 prescriptions. In total 11,562,808 prescriptions were studied, among which 5% showed interactions. Two hundred and four types of potential interactions were detected. Belladonna, phenytoin sodium, cimetidine, propranolol hydrochloride, gentamicin, acetylsalicylic acid (ASA), Antacid, theophylline and carbamazepine were the most common medications. Among them, 54% showed dynamic and 34% kinetic interactions, 11% were categorized to be both and 76% displayed rapid-onset interactions. Moderate interactions were the most dominant (70%) phenomenon. Dynamic and kinetic interactions significantly differed with respect to the onset of interactions (P < 0.001). A rather different pattern of drug-drug interaction exists in Iran, highlighting the need for a nationwide program on related education and a stronger focus on severe and rapid-onset interactions. Further studies warrant the need to explore high-risk patients.

• Spider bite (latrodectism) in Mashhad, Iran.

  Authors: R Afshari, M Khadem-Rezaiyan, M Balali-Mood

  Human & experimental toxicology. 10/2009;

  Background: Spider (Latrodectus tredecimguttatus) bites are relatively common in North East Iran. They induce morbidity and rarely mortality. We aimed to investigate clinical, electrocardiographicBackground: Spider (Latrodectus tredecimguttatus) bites are relatively common in North East Iran. They induce morbidity and rarely mortality. We aimed to investigate clinical, electrocardiographic and para-clinical changes in patients with this bite. Methods: All consecutive patients admitted with suspected spider bites between September 2005 and September 2006 were studied prospectively. Results: Spider bites accounted for 56 cases (0.5% of all poisoning, 21% of all admitted envenomated). The patients' mean (SD) age was 32 (16) years. The most common findings were pain (90%) mainly in their back (45%), stomach (35%), lower limbs (33%), upper limbs (19%) and chest (14%). Other clinical findings included were sweating (55%), chills (29%), dyspnea (25%), flushing (14%), spasm (12%), headache (12%), nausea (12%) and vertigo (12%). On electrocardiograph (ECG); ST segments were depressed in 25% of cases in at least two of the pre-cordial leads. Laboratory findings were in normal ranges. All the patients recovered following supportive and symptomatic treatment (no anti-toxin available in Iran), with a mean hospitalization period of 1.9 (1.3) days. Conclusions: Spider (L. Tredecimguttatus) bite is relatively common in Mashhad, which induces latrodectism with relatively different findings and cardiac toxicity. ECG monitoring should be considered, particularly when specific anti-toxin is not available.

• Co-proxamol overdose is associated with a 10-fold excess mortality compared with other paracetamol combination analgesics.

  Authors: R Afshari, A M Good, S R J Maxwell, D N Bateman

  British journal of clinical pharmacology. 11/2005; 60(4):444-7.

  AIMS: To assess the relative toxicity of co-proxamol in overdose in comparison to the 2 other paracetamol-opioid combination products, co-codamol and co-dydramol. METHODS: Data collected over aAIMS: To assess the relative toxicity of co-proxamol in overdose in comparison to the 2 other paracetamol-opioid combination products, co-codamol and co-dydramol. METHODS: Data collected over a 2-year period (July 2000-June 2002) was used to estimate the frequency of overdose and death for the three most popular paracetamol-opioid compound analgesics. Prescription data for Scotland and Edinburgh, the number of overdoses (derived from overdose admissions in Edinburgh) or Poisons Information Service contacts in Scotland, and national death records were used to calculate a series of indicators relating morbidity (admissions), surrogates of morbidity (poisons enquiries by telephone or internet) and mortality to prescriptions. RESULTS: When related to prescription volume overdoses involving co-proxamol in Scotland were 10 times more likely to be fatal (24.6 (19.7, 30.4)) when compared with co-codamol (2.0 (0.88, 4.0)) or co-dydramol (2.4 (0.5, 7.2)). In contrast there was no difference in the presentation rate or enquiry rates for these analgesics when corrected for prescriptions. CONCLUSIONS: The excess hazard from co-proxamol is due to inherent toxicity rather than increased use in overdose. We estimate from this study that withdrawal of co-proxamol would prevent 39 excess deaths per annum in Scotland alone.

• ECG abnormalities in co-proxamol (paracetamol/dextropropoxyphene) poisoning.

  Authors: R Afshari, S Maxwell, A Dawson, D N Bateman

  Clinical toxicology (Philadelphia, Pa.). 02/2005; 43(4):255-9.

  OBJECTIVES: 1) To investigate ECG changes following co-proxamol (paracetamol 325 mg and dextropropoxyphene 32.5 mg) overdose in comparison to co-codamol (paracetamol and codeine) or co-dydramolOBJECTIVES: 1) To investigate ECG changes following co-proxamol (paracetamol 325 mg and dextropropoxyphene 32.5 mg) overdose in comparison to co-codamol (paracetamol and codeine) or co-dydramol (paracetamol and dihydrocodeine) in a prospective study. 2) To examine the relationship between estimated dextropropoxyphene dose and ECG changes in a larger patient population. BACKGROUND: Co-proxamol is a common cause of drug-induced death and hospital admission in the United Kingdom. ECG changes following dextropropoxyphene have been reported in animals and man, including QRS prolongation. METHODS: The prospective study was conducted on 15 patients and controls with overdose. A retrospective study of a cohort of 159 co-proxamol overdoses from a combined data set from Edinburgh and Newcastle, Australia was also conducted. The measured or estimated "four hour" plasma paracetamol level was used as a surrogate of the amount of dextropropoxyphene ingested. RESULTS: In the prospective study co-proxamol overdose caused statistically significant QRS prolongation (mean [95% CI] 99.36 [96.19, 102.53] msec), compared to the other combination opioid-paracetamol products (82.84 [80.81, 84.88] msec) but no effect on PR or QTc. QRS duration increase was evident soon after exposure and remained prolonged and stable over the following 24 h. In the retrospective cohort study a dose dependency of effect on QRS was documented, although the correlation coefficient relating paracetamol level to effect was relatively weak (r = 0.338, Sig. [2-tailed] 0.003, n = 74). CONCLUSIONS: QRS is significantly prolonged in co-proxamol overdose, and this prolongation is dose dependent. These findings have clinical relevance to the management of patients with co-proxamol poisoning.

• Pattern of acute poisonings in Mashhad, Iran 1993-2000.

  Authors: R Afshari, R Majdzadeh, M Balali-Mood

  Journal of toxicology. Clinical toxicology. 02/2004; 42(7):965-75.

  Drugs and chemicals are almost easily available in Iran. Natural toxins as poisonous plants and animals also exist in most parts of the country. Therefore, acute poisonings, either intentional orDrugs and chemicals are almost easily available in Iran. Natural toxins as poisonous plants and animals also exist in most parts of the country. Therefore, acute poisonings, either intentional or accidental and also drug abuse/addiction are common in Iran. In spite of these difficulties there is no center for poison control and surveillance in this country to gather information and analyse data. The files of a systematic randomised ten percent of all hospital-referred poisoned patients from 21 March 1993 to 20 March 2000 in Imam Reza (p) University Hospital of Mashhad (71589 cases) were screened retrospectively. Young adults (40.3%) and school children (22.9%) were the most vulnerable group. Mean age was 22.3 (S.D. 14.38) years with a minimum of less than one and a maximum of 98 years old. A female predominance was found (53.4%). Intentional poisoning was more common (54.4%) than accidental exposures (45.2%). Fourteen cases were classified as criminal poisoning. 79.7% of exposures were via ingestion, followed by dermal exposures (14.1%), and inhalation (6.2%). The majority (83.7%) of patients were from urban areas. Most patients (68.6%) were treated in the Emergency Toxicology Clinic and discharged, 19.2% were temporarily hospitalized and 11.3% were hospitalized for 24 hr. Main groups of poisons were pharmaceuticals (61.4%), chemicals (22.8%), and natural toxins (16.6%). The overall number of poisoned patients was higher in spring and summer (62.8%). In conclusion, acute poisonings, particularly self-poisonings, are common in Iran. Since medical documentation is not routinely provided in this country the results of this retrospective study can be used for surveillance. Establishment of fluent data gathering and analysis within the local health system are challenges for the future.

• Co-proxamol and suicide: Licence needs to be changed.

  Authors: D N Bateman, R Afshari

  BMJ (Clinical research ed.). 09/2003; 327(7409):287.

• Effects of licence change on prescribing and poisons enquiries for antipsychotic agents in England and Scotland.

  Authors: D N Bateman, A M Good, R Afshari, C A Kelly

  British journal of clinical pharmacology. 07/2003; 55(6):596-603.

  AIMS: To examine the effect of licence change for thioridazine at the end of 2000 on the prescription of antipsychotic drugs in England and Scotland, and investigate changes in poisons informationAIMS: To examine the effect of licence change for thioridazine at the end of 2000 on the prescription of antipsychotic drugs in England and Scotland, and investigate changes in poisons information inquiries and, for Edinburgh, poisons admissions. METHODS: Prescription data for antipsychotic drugs were obtained for England and Scotland and quarterly trends examined for 2000 and 2001. Accesses to the UK National Poisons Information Service website TOXBASE for antipsychotic products were examined for the same period. For Scotland telephone enquiry data, and admission data to the Edinburgh Poisons Unit were also evaluated. Trends in poisonings were compared with prescribing change. RESULTS: In England prescriptions for thioridazine fell rapidly in 2001 from approximately 35% of market share to less than 5%, and were replaced by risperidone, chlorpromazine and olanzapine. TOXBASE accesses fell from 39.3% of antipsychotics to 4.4%. Accesses for chlorpromazine, olanzapine and risperidone increased. In Scotland prescribing of thioridazine was similar to changes in England, but it was principally replaced by chlorpromazine. These changes were mirrored by TOXBASE accesses, telephone enquiries and in-patient admissions. The ratio of TOXBASE accesses for thioridazine to prescription numbers for the drug increased after the licence change. CONCLUSIONS: Licence change produced rapid change in prescribing behaviour within 3 months. Prescribing behaviour in England and Scotland was different. Changes in prescribing were mirrored by changes in accesses for poisons information in both England and Scotland, and in Edinburgh by hospital admissions. The increase in the ratio of TOXBASE accesses to prescriptions for thioridazine suggests doctors may have become more aware of its potential toxicity.

• Hemodynamic effects of methadone and dihydrocodeine in overdose.

  Authors: R Afshari, S R J Maxwell, D N Bateman

  Clinical toxicology (Philadelphia, Pa.). 45(7):763-72.

  BACKGROUND: Opioid overdose is an increasing health problem worldwide. The cardiovascular toxicity of opioids contributes to morbidity and mortality in overdose but the hemodynamic effects of opioidsBACKGROUND: Opioid overdose is an increasing health problem worldwide. The cardiovascular toxicity of opioids contributes to morbidity and mortality in overdose but the hemodynamic effects of opioids reported in animal and human studies are contradictory. METHODS: We performed a prospective observational study of patients admitted to hospital following an overdose of methadone, dihydrocodeine, or low dose paracetamol (10 each). Basic cardiovascular indices including peripheral blood pressure, pulse rate, radial augmentation index and derived measures of aortic systolic, diastolic, pulse, and mean and end systolic pressures were measured every six hours for up to 18-23 hours after exposure or until hospital discharge. RESULTS: Dihydrocodeine and methadone significantly reduced peripheral and aortic systolic, mean and end systolic pressures. Both opioids significantly decreased peripheral pulse pressure, but only methadone decreased aortic blood pressure. Dihydrocodeine reduced systemic and aortic diastolic blood pressure, an effect not induced by methadone. Methadone significantly reduced peripheral pulse pressure. Augmentation index and heart rate, however, did not change. Both opioids decreased arterial oxygen saturation. CONCLUSION: These results suggest that dihydrocodeine and methadone in overdose both have a significant effect on central and peripheral hemodynamics. These effects might be expected to reduce cardiac afterload, providing a pharmacological explanation for the apparent benefit of opioids in cardiovascular diseases.