Brief Answer: Needs psychiatric consultation. Detailed Answer: Hello, Thanks for trusting us with your health concern. Since your son is 24 years old this is likely to be a deliberate overdose - may be for a suicide attempt. Grilinctus cough syrup contains anti allergic and dextroethorphan. This can cause an excessive sleepiness. If it has been more than an hour since he has taken the syrup then inducing a vomiting will not help. In case there is altered sensorium and he is not responding to any painful stimulus then an immediate medical help is needed. If he is only sleepy with a normal respiratory rate then it is not likely to cause any long term side effects. It is best to consult your physician in case he is not arousable from the sleep or has a difficulty in breathing. Please feel free to discuss further. I will be glad to answer the follow up queries that you have. Wishing you good health. Regards. Dr. Rakhi Tayal. For future query, you can directly approach me through my profile URL http://bit.ly/Dr-Rakhi-Tayal

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