Neurological Adverse Effects Attributable to β-Lactam Antibiotics: A Literature Review

β-lactam antibiotics are commonly prescribed antibiotic drugs. To describe the clinical characteristics, risk markers and outcomes of β-lactam antibiotic-induced neurological adverse effects, we performed a general literature review to provide updated clinical data about the most used β-lactam antibiotics. For selected drugs in each class available in France (ticarcillin, piperacillin, temocillin, ceftazidime, cefepime, cefpirome, ceftaroline, ceftobiprole, ceftolozane, ertapenem and aztreonam), a systematic literature review was performed up to April 2016 via an electronic search on PubMed. Articles that reported original data, written in French, Spanish, Portuguese or English, with available individual data for patients with neurological symptoms (such as seizure, disturbed vigilance, confusional state, myoclonia, localising signs, and/or hallucinations) after the introduction of a β-lactam antibiotic were included. The neurological adverse effects of piperacillin and ertapenem are often described as seizures and hallucinations (>50 and 25% of cases, respectively). Antibiotic treatment is often adapted to renal function (>70%), and underlying brain abnormalities are seen in one in four to one in three cases. By contrast, the neurological adverse drug reactions of ceftazidime and cefepime often include abnormal movements but few hallucinations and seizures. These reactions are associated with renal insufficiency (>80%) and doses are rarely adapted to renal function. Otherwise, it appears that monobactams do not have serious neurological adverse drug reactions and that valproic acid and carbapenem combinations should be avoided. The onset of disturbed vigilance, myoclonus, and/or seizure in a patient taking β-lactam antibiotics, especially if associated with renal insufficiency or underlying brain abnormalities, should lead physicians to suspect adverse drug reactions and to consider changes in antibacterial therapy.

Seizures as adverse events of antibiotic drugs: A systematic review

OBJECTIVE

Antibiotic drugs are commonly associated with seizures. Tailoring antibiotics to the individual risk for seizures is challenged as avoidance of certain antibiotic classes may no longer be possible due to the emergence of resistant bacteria. We performed a systematic review regarding the current evidence for seizures associated with all antibiotic classes, their underlying mechanisms, and predisposing factors.

METHODS

The medical search engine PubMed was systematically screened to identify articles in English published between 1960 and 2013. All study designs were considered and evidence was assessed.

RESULTS

We included 143 articles involving 25,712 patients and 25 different antibiotics. Evidence for antibiotic-related symptomatic seizures is low to very low, mainly deriving from studies regarding β-lactams, especially unsubstituted penicillins and fourth-generation cephalosporins, as well as carbapenems, mainly imipenem, all administered in high doses or in patients with renal dysfunction, brain lesions, or known epilepsy. Evidence regarding symptomatic seizures from fluoroquinolones only relies on case reports and case series with most reports for ciprofloxacin in patients with renal dysfunction, mental disorders, prior seizures, or coadministered theophylline.

CONCLUSIONS

Evidence for an association between antibiotic drugs and symptomatic seizures is low to very low (evidence Class III-IV). Despite this, numerous reports point to an increased risk for symptomatic seizures especially of unsubstituted penicillins, fourth-generation cephalosporins, imipenem, and ciprofloxacin in combination with renal dysfunction, brain lesions, and epilepsy. During administration of such antibiotics in patients with particular predispositions, close monitoring of serum levels is advocated. As most seizures associated with cephalosporins are nonconvulsive, continuous EEG should be considered in patients with altered levels of consciousness.