SINGAPORE – The Health Sciences Authority (HSA) warned against three weight-loss products after two users experienced adverse effects such as rapid heartbeat and extreme thirst.

These so-called “natural” or “herbal” products sold on e-commerce platform Shopee were found to contain high amounts of sibutramine, a banned toxic substance, HSA said on Jan 12.

The products are Nature Slim, Slimming Seven Days by Figure Up and Energy Booster Figure-Up New Look Strong Version.

The authority said it has worked with platform administrators to remove the listings from Shopee, and warned sellers.

A woman who took Nature Slim for two months experienced rapid heartbeat, dry mouth and extreme thirst, according to HSA.

Her friend told her that these symptoms were normal because the product was advertised as a way to enhance metabolism.

The product was marketed as a traditional and clinically proven method to lose weight and control appetite. The label also said it contained a “botanical extract”.

But after reading previous advisories by the HSA, the woman suspected her symptoms could be caused by sibutramine, so she reported it to the authorities.

Another consumer experienced dry mouth, extreme thirst and insomnia after taking Slimming Seven Days by Figure Up for a few days, HSA said. It was marketed as a natural and traditional weight loss product to help suppress appetite.

HSA said it found “very high” levels of sibutramine in Slimming Seven Days by Figure Up and Energy Booster Figure-Up New Look Strong Version.

Sibutramine is a prescription-only weight-loss medicine banned in Singapore since 2010 due to an increased risk of heart attack and stroke.

Heart problems and central nervous system disorders such as psychosis and hallucinations were some other serious health issues that have been reported after consuming the substance.

In a previous case reported to the HSA, a woman experienced an extremely fast heart rate and fell unconscious after taking a product tainted with sibutramine. She was resuscitated, but a defibrillator had to be implanted to regulate her heart rhythm.

HSA said the three weight loss products were falsely labelled with Good Manufacturing Practice logos, which may mislead consumers into believing the products are safe.

The authority said that consumers should be wary of products that promise to deliver quick weight loss or carry exaggerated claims such as “100 per cent herbal”.

It added that adulterated products are often manufactured under poor conditions with no quality control, so different batches of the same product may have different amounts of ingredients and different types of adulterants.

“These products may appear well packaged or (are) labelled as certified to meet quality standards, but these are tactics used by unscrupulous manufacturers to falsely portray that the products are safe and of good quality, when in fact they can contain potent ingredients which can seriously harm your health,” the authority said.

“If buying online, buy only from reputable pharmacies or retailers’ websites or those with an established retail presence in Singapore,” it added.

HSA said it would take stern enforcement action against anyone who sells and supplies products found to be adulterated with banned substances or potent ingredients.

Sellers and suppliers are liable to prosecution and, if convicted, may be fined up to $10,000, jailed for up to two years, or both.

Those who have information on the sale and supply of these illegal products may contact HSA’s enforcement branch on 6866-3485 during office hours or e-mail hsa_is@hsa.gov.sg