The incident occurred last night around 11.30 pm when a CISF team spotted the woman exhibiting suspicious behaviour when she arrived at the airport terminal here to travel to Addis Ababa.
The woman, identified as Lynnette Nosipho, was about to board the flight when she was intercepted.
"Nosipho was chosen for a detailed inspection by security officials and when her baggage was scanned, 16 packets containing over 19 kilograms of narcotics were found," a senior Central Industrial Security Force (CISF) officer said.
The CISF team later alerted anti-narcotics sleuths who apprehended Nosipho under relevant sections of the Narcotic Drugs and Psychotropic Substances (NDPS) Act.
"The estimated value of the seized drug is Rs 1.18 crore," the officer said.