A client with depression is started on sertraline (Zoloft). The client asks, 'How long before I feel better?' Which response is MOST accurate?

SSRI (selective serotonin reuptake inhibitor) ONSET OF ACTION is a critical patient education topic because PREMATURE DISCONTINUATION is one of the most common reasons antidepressant therapy fails. PHARMACOLOGY OVERVIEW: SSRIs block the reuptake of serotonin into the presynaptic neuron, increasing serotonin availability in the synapse. However, this IMMEDIATE CHANGE at the receptor level does not immediately translate to clinical improvement — it takes weeks for the downstream neurobiological changes (receptor downregulation, neurogenesis, BDNF changes) that correlate with symptom improvement. TIMELINE: WEEKS 1-2: may notice improvement in SLEEP (often improves first), APPETITE, and ENERGY before mood improves; WEEKS 2-4: beginning of mood improvement for many clients; FULL EFFECT: 4-8 weeks for most clients (some may take up to 12 weeks); IF NO RESPONSE by 8-12 weeks: re-evaluate with provider (dose adjustment, medication change, augmentation). INITIAL SIDE EFFECTS (often first 1-2 weeks, usually transient): nausea, GI discomfort, headache, increased anxiety (paradoxical — SSRIs can temporarily worsen anxiety before improving it), sleep disturbances, sexual dysfunction (may persist). IMPORTANT SAFETY WARNING: FDA BLACK BOX WARNING — SSRIs may increase suicidal ideation in children, adolescents, and young adults (up to age 25) particularly in the first few weeks of treatment or after dose changes; monitor closely; educate patient and family to report worsening depression, agitation, unusual behavior. DISCONTINUATION SYNDROME: abrupt stopping causes 'FINISH' symptoms — flu-like symptoms, insomnia, nausea, imbalance, sensory disturbances, hyperarousal; always taper slowly when discontinuing. NEVER instruct a client to stop medication without provider guidance.