Some medicinal mushrooms can be found alone, while others, such as cordyceps, are usually found in a mushroom combination. In either case, you may want to choose the powder over a tincture, as powders are usually more potent. If you do use a mushroom tincture, and some are very good, just make certain you shake the bottle well before taking it to get the little particles into the dropper that have the activity you’re seeking (mushrooms do not dissolve well in alcohol). If you're in a crisis, like a persistent cough or asthmatic attack, you may want to take mushrooms every hour for a few days.
Unless you have real allergy to yeasts, molds, and fungi (having an overgrowth of the yeast Candida albicans is not the same as having a yeast allergy), taking medicinal mushrooms is not only safe, it may be one of the most protective substances for seasonal illnesses.
Consider buying a pound of dried shiitake mushrooms at an Oriental market —— if one is nearby. Soak a handful of them in warm water, and add slices of them to a stir-fried dish or soup. Don’t throw away the water they soaked in, since it contains beta glucans and other immune-stimulating substances. If you like, you can freeze this mushroom-water in ice cube trays and add some to soups and sauces. Let food become your medicine, as Hippocrates suggested centuries ago, by adding medicinal mushrooms to your diet and supplement program, especially if your immune system needs support, or you tend to suffer from chronic respiratory problems.
Hobbs, Christopher, LAc. Medicinal Mushrooms, Botanica Press, 1986.
Lieberman, Shari, PhD, and Ken Babal, CN. Maitake: King of Mushrooms, Keats Publishing, 1997.
Yance, Donald R., Jr., CN, MH, AHG. Herbal Medicine, Healing & Cancer, Keats Publishing, 1999.