A client prescribed fluoxetine (Prozac) returns to the clinic one week after beginning therapy and states, "This drug is not working, I am still very sad." Which of the following would be the nurse's best response?

"We need to add another drug with this one to help."

"This drug could take 1-3 weeks to begin working."

"Let me call the provider to switch to a different antidepressant."

"This drug could take 4-6 weeks to begin working."