The signs and symptoms of acute alcohol intoxication resemble those of vertebrobasilar stroke. Due to their shared symptoms including double vision, nystagmus, dysarthria, and ataxia, the differential diagnosis of alcohol intoxication and vertebrobasilar stroke may pose a challenge. Moreover, if alcohol intoxication and stroke occur simultaneously, the signs and symptoms of stroke may be attributed to the effects of alcohol, leading to delayed stroke diagnosis and failure to perform reperfusion therapy. Three cases of alcohol intoxication and stroke are presented. The first patient (female, 50 years old) had dysarthria, nystagmus and trunk ataxia on admission. Her blood alcohol level was 2.3‰. The symptoms improved after forced diuresis, but 5.5 h later progression was observed, and the patient developed diplopia and dysphagia in addition to her initial symptoms. Angiography showed occlusion of the basilar artery. Intraarterial thrombolysis was performed. The second patient (male, 62 years old) developed diplopia, dysarthria and trunk ataxia after consuming 4-units of alcohol, and his symptoms were attributed to alcohol intoxication. Two hours later, neurological examination revealed dysphagia and mild right-sided hemiparesis, which questioned the causal relationship between the symptoms and alcohol consumption. Cerebral CT was negative, and intravenous thrombolysis was administered. The third patient (male, 55 years old) consumed 10 units of alcohol before falling asleep. Three hours later, his relatives tried to wake him up. He was unresponsive, which was attributed to alcohol intoxication. When he woke up 8 h later, right-sided hemiparesis and aphasia were observed, and cerebral CT already revealed irreversible ischemic changes. Our cases show that alcohol consumption may interfere with stroke diagnosis by mimicking the signs and symptoms of vertebrobasilar stroke. Moreover, attributing the symptoms of stroke to alcohol intoxication may delay stroke diagnosis resulting in failure of reperfusion therapy. Based on our observations we conclude that stroke should be considered in the case of worsening symptoms, dysphagia, hemiparesis and disproportionately severe signs that cannot be attributed to the amount of alcohol consumed. In the case of ambiguity, ambulance should be called, and if stroke cannot be excluded, specific therapy should be administered.

Introduction: In the majority of European countries, driving after drinking small-moderate amount of alcohol is legal. Motivated by our previous studies on cerebral hemodynamics, we aimed to study whether a small-moderate blood alcohol content (BAC), at which driving is legal in some countries (0.8 g/L), influences the neuronal activity, neurovascular coupling, and cerebral vasoreactivity. Methods: Analyses of pattern-reversal visual evoked potential (VEP) and transcranial Doppler (TCD) examinations were performed in thirty young healthy adults before and 30 min after alcohol consumption. Cerebral vasoreactivity was evaluated by breath holding test in both middle cerebral arteries. By using a visual cortex stimulation paradigm, visually evoked flow velocity response during reading was measured in both posterior cerebral arteries (PCA). Results: The BAC was 0.82 g/L and 0.94 g/L 30 and 60 min after drinking alcohol, respectively. Latency of the VEP P100 wave increased after alcohol consumption. Resting absolute flow velocity values increased, whereas pulsatility indices in the PCA decreased after alcohol ingestion, indicating vasodilation of cerebral microvessels. Breath holding index and the visually evoked maximum relative flow velocity increase in the PCA and steepness of rise of the flow velocity curve were smaller after than before alcohol consumption. Conclusion: BAC close to a legal value at which driving is allowed in some European countries inhibited the neuronal activity and resulted in dilation of cerebral arterioles. Cerebral vasodilation may explain the decrease of cerebral vasoreactivity and might contribute to the disturbance of visually evoked flow response after alcohol consumption.

Background: Intravenous thrombolysis (IVT) improves acute ischemic stroke (AIS) outcomes, but with limited success. In addition, ethanol potentiates the effect of r-tPA in ischemia models. Methods: The effect of acute alcohol consumption on IVT outcomes was investigated in a retrospective cohort study. AIS patients with detectable blood alcohol concentration (BAC) during IVT were included (alcohol group; n = 60). For each case, 3 control subjects who underwent IVT but denied alcohol consumption were matched in terms of age, sex, affected brain area, and stroke severity. Outcomes were determined using the NIHSS at 7 days and the modified Rankin scale (mRS) at 90 days. Results: Patients were younger and had a less severe stroke than in a standard stroke study. Favorable long-term outcomes (mRS 0–2) occurred significantly more frequently in the alcohol group compared to controls (90% vs. 63%, p < 0.001). However, the rates of hemorrhagic transformation were similar. Multiple logistic regression models identified elevated BAC as a significant protective factor against unfavorable short-term (OR: 0.091, 95% CI: 0.036–0.227, p < 0.001) and long-term outcomes (OR: 0.187, 95% CI: 0.066–0.535, p = 0.002). In patients with BAC > 0.2%, significantly lower NIHSS was observed at 3 and 7 days after IVT vs. in those with 0.01–0.2% ethanol levels. Conclusion: Elevated BAC is associated with improved outcomes in IVT-treated AIS without affecting safety.