The preventive and intelligence unit of Siliguri Customs seized the consignment - set to be smuggled to Bangladesh through Guwahati - Saturday night.
The driver of the truck carrying the consignment was arrested.
"The 22,800 bottles were packed in 141 cartons. Its international market price is Rs.30 lakh. The consignment was being transported to Guwahati in Assam and would have been smuggled to the neighbouring country from there," said customs lawyer Ratan Banik.
The cough syrup was camouflaged and hidden under a consignment of lac-dye and vermillion.
The arrested driver, Ravi Kant, aged around 42, originally hails from Bihar's Vaishali district.
He was Sunday presented at the Siliguri court, which remanded him to 14 days' judicial custody.
--IANS (Posted on 22-09-2013)