There is that potential.

Excerpt from:
http://www.supplementwatch.com/supa....asp?letter=All

Be aware that as a fat-soluble vitamin, vitamin A can be stored in the body and levels can build up over time. Possible toxicity can result with high dose supplementation (50,000 IU/day) leading to vomiting, headaches, joint pain, skin irritation, gastrointestinal distress and hair loss. Extreme caution should be exercised during pregnancy, as high dose vitamin A has been associated with teratogenic effects (birth defects) on the fetus of pregnant women. Maximum intake of 5000 IU of vitamin A is suggested during pregnancy. See below in Value for information about the link between vitamin A and bone fractures.

Because vitamin D is a fat-soluble vitamin, it is stored in the body and has the potential to reach toxic levels if taken in high doses for prolonged periods of time. Intakes over 1000IU (nearly 3 times the daily value) can cause nausea, diarrhea, skin rash, headaches, muscle weakness, calcium deposits and kidney stones. Prolonged sunlight exposure does not cause buildup of vitamin D as the body down-regulates its production when body levels are adequate.

You may want to switch over to an EPA/DHA supplement instead of cod liver oil. Studies have shown enormous health benefits and you needn't worry about A & D as it contains none.

There have been many posts on the subject. Check the Fish Oil Caps - YUCK thread, pages 2 & 3.