Yes, in general I would rather take something from my garden than be a guinea pig for testing out new medicines.
The herbs that have their medicinal properties built into their names, feverfew, boneset, all-heal, and all the ones with officinalis in their scientific name, have been used medicinally for probably 1000 years. That doesn't mean it will be effective for all the things the traditional medicine might claim (cure cancer etc). Back in the traditional medicine days they didn't have any OTHER medicines, so they tried all kinds of herbal stuff for serious illnesses. But it does pretty much mean it won't hurt you. For medicinal purposes I look for the ones that have traditional history AND modern science to back it up. EG:
In 1985, it was reported that extracts of feverfew inhibited the release of 2 inflammatory substances; serotonin from platelets and prostaglandin from white blood cells. Both are thought to contribute to the onset of migraine attacks and perhaps even to play a role in rheumatoid arthritis.
Migraine sufferers may have to wait several months to notice improvement, but the wait is well worth it. Some 80% of all cases have found feverfew a preventive in migraine headaches.
The active compound in Feverfew called parthenolide occurs in a variety of medicinal plants used in traditional medicine. It seems to block substances in the body that widen and constrict blood vessels and cause inflammation leading to migraines
Feverfew has also been used for centuries for arthritis. It is thought to hinder the production of prostaglandins. These are hormone-like substances that cause pain and inflammation
But NOTE: Feverfew can be taken as a tea but the medicinal compounds make it extremely bitter. It may be more palatable if mixed with some honey or taken with food.
AND Feverfew [like aspirin and other OTC pain relievers] may increase the tendency to bleed (prevent blood-clotting) so check with your health care practitioner if you are taking anticoagulants before embarking on a Feverfew treatment.
And because I love the stories behind names, I thought it was cool when I found this: Feverfew has one of the longest histories of any herb. The legend is that it was used to save the life of a ancient Greek construction worker who fell off the roof of the Parthenon. This explains the derivation of its scientific name Tanacetum parthenium.
So more than you ever wanted to know, sorry, but just using this as an example...