Background

Reishi mushroom (Ganoderma lucidum) is a bitter-tasting fungus with no proven health benefits. It is thought to have some effects on the immune system.

Reishi mushroom is used for Alzheimer disease, cancer, diabetes, cold sores, and many other conditions, but there is no good scientific evidence to support these uses.

Safety Safety definitions

When taken by mouth: Reishi mushroom extract is possibly safe when used for up to one year. Powdered whole reishi mushroom is possibly safe when used for up to 16 weeks. Reishi mushroom can cause dizziness, dry mouth, itching, nausea, stomach upset, and rash.

Special Precautions & Warnings:

Pregnancy and breast-feeding: There isn't enough reliable information to know if reishi mushroom is safe to use when pregnant or breast feeding. Stay on the safe side and avoid use.

Bleeding disorders: High doses of reishi mushroom might increase the risk of bleeding in some people with certain bleeding disorders.

Surgery: High doses of reishi mushroom might increase the risk of bleeding in some people if used before or during surgery. Stop using reishi mushroom at least 2 weeks before a scheduled surgery.

Effectiveness

Dosing & administration

Reishi mushroom has most often been used by adults in doses of 1400-5400 mg by mouth daily, usually in divided doses. Reishi mushroom extracts have also been used in lower doses. Speak with a healthcare provider to find out what dose might be best for a specific condition.

Interactions with pharmaceuticals

Medications for diabetes (Antidiabetes drugs)

Interaction Rating=Moderate Be cautious with this combination.

Reishi mushroom might lower blood sugar levels. Taking reishi mushroom along with diabetes medications might cause blood sugar to drop too low. Monitor your blood sugar closely.

Medications for high blood pressure (Antihypertensive drugs)

Interaction Rating=Moderate Be cautious with this combination.

Reishi mushroom might lower blood pressure. Taking reishi mushroom along with medications that lower blood pressure might cause blood pressure to go too low. Monitor your blood pressure closely.

Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)

Interaction Rating=Moderate Be cautious with this combination.

Reishi mushroom might slow blood clotting. Taking reishi mushroom along with medications that also slow blood clotting might increase the risk of bruising and bleeding.

Interactions with herbs & supplements

Herbs and supplements that might lower blood pressure: Reishi mushroom might lower blood pressure. Taking it with other supplements that have the same effect might cause blood pressure to drop too much. Examples of supplements with this effect include andrographis, casein peptides, L-arginine, niacin, and stinging nettle.
Herbs and supplements that might lower blood sugar: Reishi mushroom might lower blood sugar. Taking it with other supplements with similar effects might lower blood sugar too much. Examples of supplements with this effect include aloe, bitter melon, cassia cinnamon, chromium, and prickly pear cactus.
Herbs and supplements that might slow blood clotting: Reishi mushroom might slow blood clotting and increase the risk of bleeding. Taking it with other supplements with similar effects might increase the risk of bleeding in some people. Examples of supplements with this effect include garlic, ginger, ginkgo, nattokinase, and Panax ginseng.

Interactions with foods

There are no known interactions with foods.