This is still a controversia subject. If you do a web search you'll find much alarming material, mostly very biased, and not very accurate. I don't think there's much place for using ECT in ordinary depressions under ordinary circumstances. But it is considered safe and effective ( and probably more rapidly than medication ) in people with severe depressions not responding to carefully selected medications used properly. It tends to be preferred in the elderly, and, perhaps surprisingly, in people with some medical conditions or frailties. So it may be worth considering, but needs to be carefulyl discussed with his specialist psychiatrist.