This means may be overlooking potential interactions — both negative and positive — according to the head of Blackmores Institute Dr Lesley Braun.
"Pharmacists have the ideal opportunity to discuss these issues if they learn about complementary medicines," she said.
"We know that complementary medicines provide safe and effect treatment, but some can cause drug interactions. Some of these can be negative, but they can also be positive.
"Understanding that and being able to make recommendations based on the knowledge is truly integrated medicine."
Speaking at a symposium for community pharmacists in Bangkok, Dr Braun highlighted some of the positive interactions of several supplements, such as probiotics in relation to antibiotic use, improved drug tolerance provided by Coenzyme Q10 and statin, and the synergistic therapeutic effects of fish oils, also for people taking statins.
She also pinpointed how some prescription medications can alter nutrient absorption and secretion.
For example, blood pressure medication leads to an increased risk of zinc deficiency, because the body absorbs less and excretes more quickly. Likewise, the common diabetes medication Metformin has been associated with an increased risk of vitamin B12 deficiency.
"This is why pharmacists need to continually educate themselves to ensure their knowledge is up to date, and so they can disseminate this knowledge to customers," said Dr Braun, who initially trained and worked as a pharmacist.
"Also, when you learn more about this area, you can become a better pharmacist because you have a lot more solutions and build-up consumer loyalty because of your advice.”
Encouragingly, the vast majority of the Thai pharmacists surveyed appeared to want to learn more.
The research, conducted by Assistant Professor Dr Tannattha Kittisopee from Chulalongkorn University and backed by Blackmores Institute, found that 91% wanted to improve their supplement knowledge; only 21% stated their pharmacies provided a truly integrated service between prescription and complementary medicine.
Most said they had developed their supplement knowledge through textbooks, the Internet, or product leaflets.
When it comes to potential drug / supplement interactions, however, it is clear there is scope for further improvement, with under 5% surveyed stating they always or often ask patients on prescription medication if they are also taking supplements.
In order to increase the knowledge base, Blackmores Institue said it holds a number of symposiums around the region and has also produced a comprehensive drug interaction guide that is available online and in hard-copy form.
"As more people turn to complementary medicine, its really important that pharmacists can help them," said Dr Braun.
"Most of us, if we’re lucky, get around six minutes with our doctor, whereas pharmacists can get a really detailed picture of a person's lifestyle and really help them make positive behavioural changes."