Edward suffers from an extreme case of unhappiness, low self-esteem, and hopelessness. despite drug therapy he has begun talking about suicide. her therapist suggests the next treatment should be:

The answer is "Electroconvulsive therapy".

Electroconvulsive therapy (ECT) refers to a process which we can utilize to treat psychiatric conditions. This technique or procedure is considered more effectively than any other medication, as in the given case drug therapy has no effect on Edward, So now ECT should be the next treatment.