Dysgeusia is a frequent, yet underreported side effect of chemotherapy for cancer. We report here the first use of gabapentin in two glioblastoma patients who developed dysgeusia following intra-arterial administration of carboplatin or oral administration of lomustine, respectively. Treatment initiation was followed by resolution of taste alteration within weeks. Both patients reported significant improvement in their quality of life and regained weight, allowing further chemotherapy cycles. We hypothesized that in these two cases, chemotherapy impeded gustatory cells turnover and function, resulting in a gustatory “deafferentation-like” syndrome which was successfully addressed by the medication.

Restless legs syndrome (RLS) is a common neurological movement disorder, characterized by restless and unpleasant sensations in the deep inside of legs. The symptoms of RLS are less noticeable during daytime, but more prevalent at night. Therefore, the disorder can induce low quality of life, insomnia, and impairment of daytime activity. RLS in end-stage renal disease (ESRD) patients is especially problematic due to premature discontinuation of dialysis and increased mortality. The prevalence of RLS among dialysis patients is much higher compared to the prevalence of the same disorder in patients with normal renal functions. Even though there are recommended treatment guidelines for the general population established by Medical Advisory Board of the RLS foundation, which include the use of dopamine agonists, levodopa, gabapentin, benzodiazepines, and opioids, limited information is available on the effects of these therapies in ESRD patients. Since the existing clinical data were extrapolated from small sample sizes in short-term clinical trials, further clinical studies are still needed to better assess the efficacy, safety, and tolerability of these medications in patients with ESRD.

Aims: The efficacy of the anticonvulsants valproate, lamotrigine and gabapentin in bipolar disorder is reviewed.

Method: Using Medline ® and other sources of information, 12 double-blind controlled studies with either of these compounds were identified.

Results: None of the compounds has been proven effective in the prophylaxis of bipolar disorder. Valproate has been found an effective drug in acute mania, while in continuation treatment after acute mania it proved to be save, i.e. not causing switches into depression. Lamotrigine is the only anticonvulsant with proven efficacy in acute bipolar depression. So far gabapentin has not been found effective.

Conclusion: For the prophylaxis of bipolar disorder, lithium is still the treatment of choice. Carbamazepine and valproate are good alternatives, especially for patients not responding to lithium or not tolerating it. Lamotrigine may be a good alternative in bipolar depression.

The α 2 δ auxiliary subunits of voltage-gated Ca2+ channels (VGCCs) are important modulators of VGCC function. Gabapentin interacts with α 2 δ 1 and α 2 δ 2 subunits and is reported to reduce Ca2+ channel current amplitude (I Ca). This study aimed to determine the effects of gabapentin on VGCCs in retinal ganglion cells (RGCs). Whole cell patch clamp was used to record I Ca in isolated RGCs, and calcium imaging was used to measure Ca2+ transients from RGCs in situ. Immunohistochemistry was used to detect the presence of α 2 δ 1-containing VGCCs in isolated RGCs in the absence and presence of gabapentin pretreatment. Acute administration of gabapentin reduced I Ca and Ca2+ transients compared to control conditions. In isolated RGCs, pretreatment with gabapentin (4–18 h) reduced I Ca, and cell surface α 2 δ 1 staining was reduced compared to nonpretreated cells. Acute administration of gabapentin to isolated RGCs that had been pretreated further reduced I Ca. These results show that gabapentin has both short-term and long-term mechanisms to reduce I Ca in isolated RGCs. Some Ca2+ channel blockers have been shown to protect RGCs in retinal trauma suggesting that modulation of VGCCs by gabapentin may prevent the deleterious effects of elevated Ca2+ levels in RGCs in trauma and disease.

Objective: To review and summarize the currently available data on the use of anticonvulsant mood stabilizers (carbamazepine, valproic acid, gabapentin, lamotrigine, topiramate) in the treatment of behavioral and psychological symptoms of dementia (BPSD); to determine whether these medications can be recommended for routine clinical use.

Methods: Literature search in five databases (PubMed, MEDLINE, EMBASE, PsychINFO and COCHRANE collaboration) and analysis of the randomized controlled double-blinded clinical trials found therein.

Results: A total of seven RCTs were identified (two for carbamazepine and five for valproate). One study showed statistically significant improvement of BPSD in the medication group in comparison to the placebo group; five studies showed no significant differences; one study showed statistically significant worsening of the symptoms in the medication group vs. placebo. The majority of the studies reported significantly more frequent adverse effects in the medication group.

Conclusion: Although clearly beneficial in some patients, anticonvulsant mood stabilizers cannot be recommended for routine use in the treatment of BPSD at the present time.

Summary

Background and objective: We have compared the effects of gabapentin on arterial pressure and heart rate at induction of anaesthesia and tracheal intubation in a randomized double-blind study. Methods: Ninety normotensive patients (ASA I) undergoing elective surgery were divided into three groups of 30 patients each. Patients received oral placebo (Group I), 400 mg of gabapentin (Group II) or 800 mg of gabapentin (Group III) 1 h prior to surgery in the operating theatre. After induction of anaesthesia heart rate and mean arterial pressure were recorded at baseline 1, 3, 5, 10 and 15 min after intubation. Results: Patients receiving placebo and 400 mg gabapentin showed a significant increase in blood pressure and heart rate associated with tracheal intubation compared to baseline levels and Group III. There was significant decrease in heart rate and arterial pressure in Group III after intubation 1, 3, 5 and 10 min (P < 0.001, P < 0.001, P < 0.05 and P < 0.05, respectively) compared to Groups I and II. Conclusion: Given 1 h before operation gabapentin 800 mg blunted the arterial pressure and heart rate increase in first 10 min due to endotracheal intubation. Oral administration of gabapentin 800 mg before induction of anaesthesia is a simple and practical method for attenuating pressor response to laryngoscopy and tracheal intubation after standard elective induction.