High doses of fish oil can also cause pro-inflammatory effects. It can also increase bleeding time, interfere with wound healing, worsen diatetes and impair imune function. Adding Vitamin E and a B complex vitamin wil help the situation but not eliminate the problem.
"When the body has as much DHA as it needs, feedback inhibition stops further conversion. Without this inhibition, toxicity could result from excess DHA production. Let me give an example. An analysis of fish oil studies showed that too much fish oil increases inflammation due to the extreme sensitivity of DHA to damage caused by oxidative stress [4]. Giving n-3 in the more stable form of ALA is safer because it gives the body better metabolic control and prevents DHA overdosing. Some prominent Canadian health researchers have stated for more than 10 years that they prefer the basic n-3 ALA to fish oils because of this better metabolic control that ALA affords the body."
Arnesen H N-3 fatty acids and revascularization procedures. Lipids. 2001;36 Suppl:S103-6. Review.
Measurement of persistent organic pollutants in 15 commercial fish oils. 2002. Central Science Labs in the UK carried out the tests for PCBs, PAHs, and dioxins.
So replacing his Flax (which is usually about 1-3 Tablspoons /day (14-42g/day) is complete overkill and not necessary at all.