Question 1

What do PHQ-9 scores mean and what action should be taken at each level?

Accepted Answer

PHQ-9 scores are interpreted as follows: 0–4 = minimal/none (no action, monitor); 5–9 = mild depression (watchful waiting, self-help, review in 2–4 weeks); 10–14 = moderate depression (consider antidepressant or structured psychotherapy such as CBT, review within 2 weeks of starting treatment); 15–19 = moderately severe (antidepressant + refer for psychotherapy, review at 2 weeks); 20–27 = severe depression (antidepressant + urgent referral to CMHT or secondary care, consider crisis assessment). A score ≥1 on Question 9 (suicidal ideation) always requires immediate risk assessment regardless of total score.

Question 2

When should a GP start antidepressants for depression?

Accepted Answer

According to NICE NG222, antidepressants should be offered when: (1) PHQ-9 score is ≥10 (moderate depression) and the patient prefers medication over psychological therapy; (2) there is moderate-to-severe depression with significant functional impairment; (3) previous episodes responded well to antidepressants; or (4) psychological therapy is unavailable or declined. For mild depression (PHQ-9 5–9), antidepressants are not first-line — guided self-help and active monitoring are preferred. First-line choice is an SSRI (sertraline 50 mg or citalopram 20 mg). Always review at 2 weeks after initiation; warn patients of initial anxiety and 4–6 weeks before full therapeutic effect.

Question 3

What are the lithium monitoring requirements in primary care?

Accepted Answer

Lithium has a narrow therapeutic index (0.4–1.0 mmol/L; aim 0.6–0.8 mmol/L for maintenance, 0.8–1.0 mmol/L for acute mania). Monitoring schedule: Check lithium level 12 hours post-dose at initiation, after every dose change, and then every 3–6 months when stable. Also monitor: renal function (eGFR, urea, creatinine) and thyroid function (TSH) every 6 months — lithium causes hypothyroidism in up to 40% of long-term users. Check ECG at baseline (can cause T-wave changes and sinus node dysfunction). Toxicity signs (level >1.5 mmol/L): coarse tremor, vomiting, diarrhoea, drowsiness, ataxia, confusion — treat as emergency. Caution with NSAIDs, diuretics (especially thiazides), and ACE inhibitors as they all raise lithium levels.

Question 4

What is the first-line antidepressant for depression in primary care and how do SSRIs compare to SNRIs?

Accepted Answer

First-line: Sertraline (50 mg daily, titrate to 200 mg) is preferred in most patients due to its favourable safety profile, low drug interaction potential, and safety in cardiac disease. Citalopram (20 mg, max 40 mg; 20 mg in over-65s) is an alternative. SSRIs vs SNRIs: SSRIs (sertraline, citalopram, escitalopram, fluoxetine) are first-line for depression and anxiety disorders with a better tolerability profile. SNRIs (venlafaxine, duloxetine) are used when SSRIs have failed, when there is comorbid chronic pain (duloxetine preferred — also licensed for diabetic neuropathy), or when a more noradrenergic effect is clinically desired. Venlafaxine can raise blood pressure and requires monitoring. Duloxetine is the SNRI of choice for generalised anxiety disorder and diabetic neuropathic pain.

Question 5

How long should antidepressants be continued after remission from depression?

Accepted Answer

NICE NG222 recommends continuing antidepressants for at least 6 months after remission of a first depressive episode — stopping earlier carries a high relapse risk. For patients with two or more previous episodes, or those with residual symptoms or chronic depression, continue for at least 2 years. Discontinue gradually over 4 weeks minimum (some guidelines suggest taper over months) to reduce discontinuation syndrome (FINISH mnemonic: Flu-like symptoms, Insomnia, Nausea, Imbalance, Sensory disturbances, Hyperarousal). Fluoxetine has the lowest discontinuation risk due to its long half-life. Always review and discuss with the patient before stopping.

Question 6

What GAD-7 score indicates generalised anxiety disorder and when should treatment be escalated?

Accepted Answer

GAD-7 interpretation: 0–4 = minimal anxiety; 5–9 = mild (low-intensity self-help, psychoeducation); 10–14 = moderate (offer high-intensity CBT or an SSRI — NICE NG197 recommends sertraline as first-line); ≥15 = severe (high-intensity CBT plus medication, consider psychiatric referral). Escalate treatment if: initial response to step-2 treatment is inadequate after 6–8 weeks, there is significant functional impairment, comorbid depression is present, or there is a risk of self-harm. Pregabalin is second-line for GAD in adults who have not responded to two sequential drug trials. Benzodiazepines should NOT be used long-term — maximum 2–4 weeks in crisis only.

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