SINGAPORE - The Health Sciences Authority (HSA) has warned the public not to buy or take three "health products" which have caused serious side effects in people who consumed them.

The three products are Ananda Thukha Remedy for Diabetes, 1 Day Diet and Bee Brand Qi Li Xiang. All three have been found to contain undeclared potent Western medicine.

A woman in her 60s who consumed Ananda Thukha Remedy for Diabetes saw her doctor for sore throat and tiredness after taking it for about three months.

The pellets, which were marketed as a cure for diabetes, were bought at a shop in Peninsula Plaza.

She was diagnosed with agranulocytosis, a serious blood disorder, HSA said.

"The patient has a low white blood cell count and is prone to fall sick from infections. She was hospitalised for almost two weeks."

HSA has seized all the implicated products from the shop for further investigation.

It was found to contain glibenclamide, a prescription-only medicine for diabetes. It may cause adverse effects such as very low blood sugar levels and certain blood disorders in rare cases.

It also contains yohimbine, a potent Western medicinal ingredient which has been associated with insomnia, anxiety, heart palpitations, sweating and blurred vision.

1 Day Diet contains sibutramine, a prescription weight loss drug disallowed for sale in Singapore since 2010.

The use of sibutramine may cause high blood pressure, irregular heartbeats, hallucinations and mood swings.

A healthy woman in her 30s experienced breathing difficulties, increased heart rate, and excessive sweating of palms after consuming 1 Day Diet capsules for less than two weeks.

Bee Brand Qi Li Xiang was purchased overseas by a woman for her husband in his 50s, who was suffering from body aches.

He took it for about a month. Soon after stopping the product, the man experienced low blood pressure and low levels of cortisol, a hormone that helps to regulate metabolism.

These are symptoms associated with steroid consumption, and could lead to serious health complications if left untreated.

The pills were found to contain dexamethasone, a potent steroid.

HSA said that long term use of an oral steroid without medical supervision can cause high blood pressure, cataracts, an increased risk of infections, and Cushing's syndrome, characterised by the appearance of round face or "moon face" and upper body obesity with thin limbs.

"Consumers need to be wary of complementary health products that offer quick cures and relief of chronic illnesses. Do not be enticed by their false promises as they may contain undeclared potent ingredients that can pose serious health risks," said Associate Professor Chan Cheng Leng, acting group director of the health products regulation.

Those who have purchased or who are currently consuming these products are advised to:

- Stop consuming them immediately, and consult a doctor if you are feeling unwell.

- As Bee Brand Qi Li Xiang contains a potent steroid, consumers should see a doctor as soon as possible. Discontinuation of steroids without proper medical supervision can cause serious withdrawal symptoms such as fatigue, confusion and low blood pressure, especially when these products have been taken for more than a few weeks.

- Exercise caution when purchasing health products online or from other sources which you may not be familiar with, even if from well-meaning friends and relatives. If buying online, consumers should buy them only from websites with an established retail presence in Singapore.

Anyone convicted of selling illegal health products can be fined up to $100,000 and/or jailed up to three years under the Health Products Act.

They face a penalty fine of up to $10,000 and/or jail of up to two years under the Poisons Act and a penalty fine of up to $5,000 and/or jail of up to two years under the Medicines Act.