Use of meropenem to treat valproic acid overdose

Carbapenems as Antidotes for the Management of Acute Valproic Acid Poisoning

INTRODUCTION

Valproic acid (VPA) is a broad-spectrum drug primarily used in the treatment of epilepsy and bipolar disorder. It is not an uncommon occurrence for VPA to cause intoxication. The established treatment of VPA poisoning includes supportive care, multiple doses of activated charcoal, levocarnitine and hemodialysis/hemoperfusion. There is a clinically significant interaction between carbapenem antibiotics and VPA. By affecting enterohepatic recirculation, carbapenems can increase the overall VPA clearance from the blood of intoxicated patients. It is suggested that carbapenems could successfully be used as antidotes in the treatment of acute VPA poisonings.

THE AIM

To evaluate the effectiveness of carbapenems in the treatment of patients acutely poisoned by VPA.

PATIENTS AND METHODS

This retrospective study included patients acutely poisoned by VPA and treated with carbapenems at the Department of Clinical Toxicology at the Military Medicinal Academy in Serbia for a two-year period.

RESULTS

After the admission, blood concentrations of VPA kept increasing, reaching their peak at 114-724 mg/L, while the mental state of the patients continued to decline, prompting a decision to introduce carbapenems. After the introduction of carbapenems, the concentrations of the drug dropped by 46-93.59% (average 72%) followed by rapid recovery of consciousness. Ten out of eleven patients had positive outcomes, while one patient died. The most commonly observed complication in our group of patients was bronchopneumonia.

CONCLUSIONS

The application of carbapenems for the management of acute VPA poisoning might be a useful and effective treatment option.

Rescue strategies for valproic acid overdose poisoning: Case series and literature review

Valproic acid (VPA) is a wide-ranging anti-epileptic medication that primarily affects bipolar disorder, mania, and migraine. The leading causes of mortality associated with acute poisoning from VPA are nervous system toxicity, drug-induced shock due to encephalopathy from hyperammonemia, as well as acute liver and kidney failure, and respiratory depression that contribute to hemodynamic instability. Treatment of acute VPA poisoning primarily involves in vitro elimination methods, including hemoperfusion (HP), hemodialysis, and hemofiltration, as well as drug remedies such as L-carnitine and meropenem. Nonetheless, there are conflicting opinions regarding drug usage. This article details the three cases of acute poisoning from VPA. The fundamental approach to treatment employs HP assisted by blood concentration monitoring to alleviate shock and stabilize hemodynamics. This investigation presents guidance for the treatment and management of acute poisoning with VPA in clinical settings.

A carbapenem antibiotic inhibiting a mammalian serine protease: structure of the acylaminoacyl peptidase-meropenem complex

The structure of porcine AAP (pAAP) in a covalently bound complex with meropenem was determined by cryo-EM to 2.1 Å resolution, showing the mammalian serine-protease inhibited by a carbapenem antibiotic. AAP is a modulator of the ubiquitin-proteasome degradation system and the site of a drug-drug interaction between the widely used antipsychotic, valproate and carbapenems. The active form of pAAP - a toroidal tetramer - binds four meropenem molecules covalently linked to the catalytic Ser587 of the serine-protease triad, in an acyl-enzyme state. AAP is hindered from fully processing the antibiotic by the displacement and protonation of His707 of the catalytic triad. We show that AAP is made susceptible to the association by its unusually sheltered active pockets and flexible catalytic triads, while the carbapenems possess sufficiently small substituents on their β-lactam rings to fit into the shallow substrate-specificity pocket of the enzyme.

Meropenem to Treat Valproic Acid Intoxication

ABSTRACT

This therapeutic drug monitoring (TDM) grand round describes a patient with serious valproic acid intoxication. A total valproic acid level of 844 mg/L and an unbound valproic acid level of 604 mg/L were observed. Meropenem was administered to enhance the clearance of valproic acid. This off-label usage of meropenem is based on the drug-drug interaction between carbapenems and valproic acid, which reduced the level of valproic acid within 24 hours after administration.

Relationship between tracheal intubation and the drugs used by patients with drug overdose due to self-harm

Background

Tracheal intubation may be performed in patients with drug overdose due to self-harm; however, the details of the causative drug are unknown. The purpose of this study was to clarify the relationship between drugs or its blood levels of patients with drug overdose and the need for tracheal intubation based on the actual measurement results.

Methods

From October 2018 to March 2020, 132 patients with drug overdose due to self-harm who were transported to the emergency department (ED) were studied. Patient drugs were measured using gas chromatography–mass spectrometry (GC-MS) and were analyzed on the basis of the GC/MS Forensic Toxicological Database. Logistic analysis was performed by combining patient information and GC-MS information.

Results

The Glasgow Coma Scale (GCS) and Japan Coma Scale (JCS) efficiently predicted tracheal intubation in patients with drug overdose during transport triage; GCS (cut-off value: 12, area under the curve (AUC): 0.81, 95% confidence interval (CI): 0.71–0.88, sensitivity: 0.85, specificity: 0.71, P < 0.05) and JCS (cut-off value: 3, AUC: 0.74, 95% CI: 0.60–0.84, sensitivity: 0.60, specificity: 0.84, P < 0.05). The drugs detected in all patients with drug overdose in order were benzodiazepine receptor agonists (BZs; 43.9%), anticonvulsants (38.6%), antipsychotics (25.0%), and antidepressants (9.8%). In univariate logistic analysis, antipsychotics (odds ratio (OR) 2.46, 95% CI 1.19–5.20, P < 0.05), anticonvulsants (OR 2.71, 95% CI 1.26–5.98, P < 0.05), and anticonvulsants above alert blood levels (OR 27.8, 95% CI 2.92–264.1, P < 0.05) were significantly associated with tracheal intubation in patients with drug overdose, but not BZs and antidepressants. Also, in multivariate logistic analysis, antipsychotics (OR 2.27, 95% CI 1.07–4.83, P < 0.05), anticonvulsants (OR 2.50, 95% CI 1.14–5.64, P < 0.05) and in multivariate logistic analysis of blood levels, anticonvulsants above the alert blood levels (OR 24.9, 95% CI 2.56–241.6, P < 0.05) were significantly associated with tracheal intubation in patients with drug overdose respectively.

Conclusions

Logistic analysis revealed that the use of anticonvulsants and antipsychotics were significantly associated with an increased OR in the tracheal intubation of patients with drug overdose due to self-harm.

A Retrospective Case Series of Concomitant Carbapenem and Valproic Acid Use: Are Best Practice Advisories Working?

Background: A Best Practice Advisory (BPA) warns clinicians of an interaction between carbapenems and valproic acid (VPA) that can cause significant declines in VPA levels leading to serious consequences for patients treated for seizure disorder and unknown implications for alternative indications. Objective: The goal of this study was to assess BPA efficacy in avoiding concomitant VPA/carbapenems, and to characterize use of these agents, clinical implications, and potential alternative therapeutic options. Methods: Retrospective chart review was performed on all patients over the course of 1 year who were concomitantly prescribed a carbapenem and VPA at Hartford Hospital, Hartford, CT. Data collected included: level of care, duration of concomitant therapy, indications, VPA levels during or surrounding overlap, documentation of the interaction, and therapeutic implications. Results: Carbapenems and VPA were administered to 591 and 625 patients, respectively; the BPA fired 126 times in 24 patients, and 15 patients were initiated on these agents concomitantly. Eight (53%) patients received VPA for seizures. The remaining seven (47%) received VPA for alternative indications. Eight of nine VPA levels were sub-therapeutic during carbapenem therapy and polypharmacy was administered in all patients receiving VPA for non-convulsive indications. Conclusion: Co-prescribing of these drugs was rare; however, the BPA was ineffective in 63% of instances. Reductions in VPA efficacy for any indication should be expected with concomitant carbapenem administration. Antibiotics other than carbapenems should be considered when coverage of multidrug resistant Gram-negative pathogens is required in patients whose VPA treatment cannot be interrupted or switched to a therapeutic alternative.

Treatment of valproic acid overdose with meropenem in an epileptic patient: A case report and literature review

Valproic acid (VPA) and derivatives are effective anticonvulsants that are also used for numerous mood disorders. VPA toxicity can cause central nervous system (CNS) depression, dose related hyperammonemia, and eventually hepatotoxicity. While traditional treatment of VPA toxicity often includes l-carnitine, activated charcoal, and hemodialysis; an interaction with carbapenem class antibiotics has been well established in literature and may offer a different avenue of treatment. This case describes a 38 year-old female with a past medical history of epilepsy effectively treated with meropenem to rapidly and safely lower toxic VPA levels after an acute ingestion. A review of four VPA poisoning case reports and the interaction with carbapenem class antibiotics is also included.

Thinking out of the box: management of valproic acid toxicity with carbapenems

Valproic acid (VPA) is commonly used medication to treat seizure disorder and as prophylaxis for bipolar disorder. Acute VPA toxicity can cause varied symptoms ranging from mild drowsiness to severe cerebral oedema and coma. The therapeutic level of VPA is around 50-100 µg/mL and most of it is protein bound. It is mainly metabolised by liver and is eliminated via bile. The metabolites of VPA interfere with urea cycle and cause deficiency in carnitine leading to increase in ammonia levels. The use of carnitine to treat VPA toxicity is well known but it is still unclear if it lowers VPA levels. We report a case of VPA toxicity that did not respond to use of carnitine at 6000 mg orally but was successfully treated using meropenem leading to lowering of VPA levels and also clinical improvement of patient.

Effect of drug interactions between carbapenems and valproate on serum valproate concentration: a systematic review and meta-analysis

Background: Concurrent use of valproate and carbapenem antibiotics may decrease serum valproate concentration (SVC). This study evaluated the effects of carbapenem-valproate drug interactions. Research design and methods: We screened PubMed, EMBASE, and Cochrane databases for eligible prospective or retrospective studies that evaluated the effect of concurrent use of carbapenem and valproate compared with valproate alone on SVC. Primary outcomes were the change in SVC from before the addition of the carbapenem to the SVC during the use of carbapenems and after carbapenem discontinuation, and seizure-related outcomes. Secondary outcomes were the influence of valproate or carbapenem dose on SVC and Drug Interaction Probability Scale scores. Results: Twelve studies (633 patients) were included. Compared with valproate alone, combination treatment with carbapenem substantially decreased mean SVC (mean difference, -43.98 mg/L; 95% confidence interval, -48.18 to -39.78). The onset of SVC decreases was within 1-3 days following carbapenem initiation. Seizure frequency increased by 26.3% during combination treatment. No difference was found in mean SVC between the different doses of valproate or carbapenem during combination treatment. Mean SVC increased to similar pre-carbapenem level within 1 to 2 weeks after carbapenem discontinuation. Conclusions: The drug interaction between valproate and carbapenem causes substantial SVC decreases, even to subtherapeutic levels, which may increase the risk of seizures.

Meropenem for management of valproic acid overdose: a case report

Objectives Valproic acid (VPA) is an anticonvulsant used in several clinical scenarios. VPA has been increasingly associated with intentional or unintentional overdose. In patients presenting with severe VPA overdose, supportive care and airway protection are cornerstones of treatment, while levocarnitine is suggested in patients with hyperammonemia and hemodialysis is recommended in patients with VPA serum concentrations (SC) >1,300 mg/L and presence of cerebral edema or shock. Meropenem is a carbapenem antibiotic with a broad spectrum of activity. The pharmacological interaction between VPA and meropenem is characterized by a rapid decrease in VPA concentrations, which contraindicates concurrent use. Case presentation The following case report describes the use of meropenem to enhance the clearance of VPA in the case of severe VPA overdose. A patient with altered mental status was transported to the emergency department (ED) after VPA overdose. Meropenem was prescribed for significant elevated VPA SC. An important decline in SC was observed with short-term meropenem dosing, and an improvement in mental status occurred shortly after administration. Conclusions Carbapenem therapy has the potential to be used as last line strategy in the management of severe VPA overdose in patients where SC represent a significant risk of toxicity and clinical symptoms suggest difficulty managing the patient.