Stroke is one of the most important causes of mortality and disability both in developed and developing countries. The only food and drug administration (FDA) approved therapy for acute stroke is recombinant tissue plasminogen activator (rtPA). But narrow therapeutic window has limited the usefulness of thrombolytic therapy. Therefore, finding effective neuroprotective drugs for the patients for whom thrombolysis is contraindicated or not feasible seemed to be mandatory in the world of cerebrovascular medicine.

Licorice, extracted from root of a plant scientifically known as Glycyrrhiza glabra, is used in food industries. Certain medical properties has been contributed to licorice and specifically to its active chemical components such as flavonoids and glycyrrhizic acid (GA). GA has been revealed to assert its anti-inflammatory effect by suppression of NF-κB, a key component of lipopolysaccharide-induced inflammatory response. Neuroprotective characteristics of GA has been widely investigated in recent studies.

In the present study, the investigators verified the efficacy and safety of oral administration of two different doses licorice extract in the patients with acute ischemic stroke, in a double-blind randomized controlled trial.

Inclusion Criteria:

• Symptoms of acute ischemic stroke
• ROSIER score higher than 2
• Confirmation of ischemic brain damage in CT scan

Exclusion Criteria:

• Clinically relevant preexisting neurological deficit or previous CVA
• Primary intracerebral hemorrhage
• Coma (level of consciousness more than 2 in NIHSS scale).
• Negative swallow test
• Patients undergoing hemicraniectomy
• History of epilepsy
• Clinical seizure at onset of stroke
• Systolic BP is >160 mmHg, diastolic BP>110 at onset of stroke (if a rise in blood pressure occurred in the course of study it was controlled according to medical guidelines)
• Atrial fibrillation or other tachy/bradyarrythmias at time of allocation or in the middle of intervention
• Ejection Fraction less than 45%
• Potassium less than 4 mEq/dl at onset of stroke
• Malignancy or premalignant state within 5 years
• Myocardial infarction in previous month
• Significant kidney disease (creatinine higher than 1.8 mg/dl)
• Significant liver disease (Bilirubin > 20 mmoll/L)
• Significant lung disease (FEV1 < 1.5 L, pO2 < 70 in room air, pCO2 > 45)
• Psychiatric illness requiring hospital admission
• Warfarin intake
• Digoxin intake
• Pregnancy
• Breast feeding
• Inability to have follow/up