A batch of the children's cough syrup manufactured by Johnson & Johnson in 2021 has now been recalled by drug authorities in six African countries.

This is after Nigeria's drug agency warned that it contained high levels of a toxic and potentially fatal substance.

Drug regulators in Tanzania and Zimbabwe are the latest to recall the syrup as a precautionary measure, although Zimbabwe's Medicines Control Authority said there was no record of the syrup being imported into the country.

Last week, Nigeria's National Agency for Food and Drugs Administration and Control (NAFDAC) recalled a batch of the Benylin Pediatric syrup after detecting the toxic substance Diethylene glycol in it.

A few days later, Kenya's pharmacy board ordered a halt in the sale of the syrup, acting on NAFDAC's advice.

They were then followed by drug authorities in South Africa and Rwanda, who recalled the syrup during the weekend.

Diethylene glycol has been linked to the recent deaths of dozens of children in Cameroon and The Gambia.

Human consumption of the substance causes multiple adverse effects, including acute kidney injury, which may lead to death.

The recalled Benylin Paediatric syrup, batch no 329304 was manufactured in South Africa in May 2021 and was marked with an expiry date of April 2024.

South Africa's drug regulator said batch 329303 was also affected, and that the batches had been sold in South Africa, Eswatini, Rwanda, Kenya, Tanzania and Nigeria.

Kenvue, which now owns the Benylin Paediatric syrup brand, said it is collaborating with authorities and conducting its own tests, Reuters news agency reported.