When it comes to herbals, if it's natural it must be safe, right? Wrong. Just because a supplement is labelled natural does not necessarily mean it's healthy.

Pharmacist Heather Boon visited with Balance Television host Dr. Marla Shapiro to talk about mixing natural and conventional medications.

So how can you know what's good, what's not and what can interact in a harmful way?

"Unfortunately, that's not an easy question to answer," admits Boon, co-author of 50 Most Common Medicinal Herbs. "In this area...patients have to do their own research. I encourage them to talk to their pharmacist and to their physician about this but there's a lot of information that we still don't know about many of these herbs."

Ginkgo
There is some evidence that ginkgo may help people who have memory impairment associated with different types of dementia such as Alzheimer's disease, Boon said. But if you don't already have memory impairment, there isn't a lot of evidence right now to suggest that ginkgo will have a significant effect on your memory. Forgetting where your car keys are in the morning doesn't count as memory impairment, she laughed.

She did note that ginkgo can effect your blood's ability to clot. So, if you're taking any other medication such as ASA, that also decreases your blood's ability to clot, then ginkgo can have an additive effect and you can increase this effect more than anticipated.

Doses
From one bottle of ginkgo to another, or one brand to another, you cannot expect to find a standardized dose, Boon said. Much of it depends on the manufacturer's process of taking the actual ginkgo herb and turning it into pill form.

Garlic
A relatively safe herb, garlic does have the same sort of cautions as ginkgo because it can also effect the blood's ability to clot. Typically, it is recommended that if a person is going into elective surgery, that they stop taking garlic a week or two before the surgery so they don't bleed more than is expected.

St. John's Wort
"It does seem to be effective for mild to moderate depression," Boon said. "However if you have severe depression, there is no evidence right now that it will work for you."

It does have many of the same adverse effects as conventional anti-depressants and overall it interacts with a number of drugs and increases the body's metabolism of those drugs.

"For example if you take it together with the birth control pill, you will metabolize the birth control pill faster," she said. "There are a couple of cases where women actually became pregnant when they took the two together."

Ephedrine
When it comes to ephedrine -- from the genus Ephedra -- the biggest concern is the dose because, Boon said, people just take far too much of it. If you take too much you can cause heart palpatations and increased blood pressure.

There have been a few deaths associated with overdoses of ephedrine so Health Canada has put out warnings about the dosage in each tablet. Unfortunately, some people don't heed those warnings.

Remember to do your research so you can be an educated, and healthy, consumer.

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