I'm taking ginkgo biloba+ginseng combo daily. can i add cod liver oil (vitamin d) to it? are there any risks?

Yes. no.: There would be no expected interaction from adding the Cod Liver Oil or vitamin D. Be sure to let your physician know that you are taking these natural supplements whenever you visit for a well check up.

OK to add vit D: Vitamin D as in cod liver oil is certainly safe to add to Gingko Biloba and Ginseng.

Depends: As long as you are not on anticoagulation ginkgo and ginseng can be taken with limited issues. Be careful with cod liver oil as while it may provide vitamin D and vitamin A, there are better sources of vitamin D. Vitamin A is a particularly finicky vitamin where too much and too little really can create problems, so it much benefit you to avoid supplementation without a known deficiency.