Biomedical subjects

A Sánchez-Romero

Publications and source records attributed to A Sánchez-Romero.

4 recordsLinked to original sources

PubMed1997

[Monitoring of gentamycin serum concentration in neonates. Usefulness in adjustment of dosage].

OBJECTIVE: The objective of this study was to confirm the variation of the pharmacokinetic parameters of gentamicin in neonates and to establish guidelines for a dosage regimen. PATIENTS AND METHODS: A study was made of 89 neonates being treated with gentamicin. The gestational ages ranged from 25 to 41 weeks and the postnatal age between 1 and 30 days. Weights were between 600 and 4,400 grams. The average dose was 2.45 +/- 0.4 mg/kg/dose. Groups were established according to gestational age (under 34 weeks, 34-37 weeks and over 37 weeks) and postnatal age (over and under 7 days old). RESULTS: The elimination half-life (t1/2) was significantly reduced (p < 0.01) in the different age groups. The distribution volume (V) showed a slight decrease corresponding to the gestational age, but this was not significant. The results suggest that the dosages applied in mg/kg were sufficient to attain potentially therapeutic peak blood levels (Cmax). However, the dosage should be administered at different intervals according to the age groups in order to allow the trough levels (Cmin) to come down to values which are considered to be therapeutic. CONCLUSIONS: An interval of 24 hours is recommended for preterm babies with a postnatal age of less than 7 days and an interval of 12 hours for the remainder of the infant population.

Anti-Bacterial Agents↗

PubMedDate not supplied

[Possible gabapentin phenytoin interaction].

INTRODUCTION: We report a possible case of gabapentin induced phenytoin toxicity. CASE REPORT: White man, 26 years old, chronically treated with phenytoin (for the past 4 years) and gabapentin (for the past 17 months). He was seen after complaining of dysarthria, ataxia and vertigo for the past 3 months, although having noted slight dizziness and a general, though undefined, indisposition from the start of taking gabapentin. The total and free serum levels of phenytoin found were clearly toxic. Gabapentin was discontinued definitively, and phenytoin for the next 7 days. The clinical symptoms had disappeared completely and phenytoin returned to within therapeutic levels. According to the criteria of causation it can be considered a possible adverse reaction caused by phenytoin related to incorporation of gabapentin. The mechanisms of this possible drug interaction are discussed, with emphasis on cytochrome P450 metabolism. CONCLUSION: The present case is a warning of the possible interaction of a drug (gabapentin) not contemplated when starting or when monitoring an antiepileptic treatment.

Acetates↗

PubMedDate not supplied

[Can treatment associated with ticlopidine and nifedipine increase serum levels of phenobarbital?].

INTRODUCTION: We report a case in which the association between ticlopidine, nifedipine and phenobarbital was linked with a higher than expected phenobarbital concentration in serum, which suggested a possible interaction between these drugs. CASE REPORT: A 67 year old male who received treatment with phenobarbital, digoxin, nifedipine, ticlopidine, paroxetine and clorazepate dipotassium. The first control of the level of phenobarbital in serum was performed without any symptoms or signs of toxicity or ineffectiveness. A phenobarbital concentration in serum of 21.4 mg/L was obtained, with a serum level/dosage ratio of 16.7. DISCUSSION: The serum level/dosage ratio of phenobarbital that was found in this case is almost twice as high as expected. In the absence of other factors that can explain this finding, we believe that two drugs (ticlopidine and nifedipine) may be involved in an interaction with phenobarbital. CONCLUSIONS: The high value of the serum level/dosage ratio that was found makes it advisable to monitor the concentrations of phenobarbital in serum in treatment associated with ticlopidine or nifedipine, especially when adjusting the dosage, beginning or ending treatment with these drugs.

Aged↗

PubMedDate not supplied

[Calculating how long phenytoin intoxication lasts].

INTRODUCTION: We report a case of intoxication with phenytoin (DPH), in which the actual time required for it to disappear was compared with that estimated using linear regression. CASE REPORT: A 23-year-old female with tonic-clonic seizures, receiving chronic therapy with DPH 300 mg/day. The patient came to hospital because of tremors, balance disorders, vomiting and headaches. Neurologically, she presented horizontal nystagmus in the two extreme gazes, generalised hyperreflexia and ataxic gait. Cranial CAT scan and cerebrospinal fluid were both normal. Serum concentration of DPH was found to be 60.2 mg/L. When DPH concentration is >8-10 mg/L, its rate of elimination diminishes disproportionately and the risk of toxicity increases. Use of mathematical methods makes it possible to calculate the time required for a toxic concentration to come down to therapeutic values. In our patient the DPH took 204 hours to drop below the toxic level (20 mg/L), whereas by using a linear regression with only two different concentrations a figure of 155 hours was obtained. CONCLUSIONS: The method employed here can be useful as a quick, simple and easily applicable way of estimating the time a toxic concentration of DPH takes to return to a normal level.

Adult↗