Pharmacologic Management of Major Depressive Disorder in Primary Care: An Algorithm for Partial Response, Switching, and Augmentation

Defining the Scope and Clinical Boundaries of the Algorithm

This algorithm is designed for adults with presumed nonpsychotic unipolar major depressive disorder who are being treated in a primary care setting and have not yet achieved remission with an initial antidepressant. It specifically addresses dose optimization, switching strategies, and augmentation. It is not intended to serve as a complete first-line prescribing guide, nor is it a protocol for advanced interventions like electroconvulsive therapy, transcranial magnetic stimulation, esketamine, or intravenous ketamine. [1-4]

Furthermore, this algorithm should not be used as a routine medication pathway when bipolar disorder, a psychotic disorder, catatonia, substance-induced depression, or a primary medical cause is the more likely diagnosis. Special populations, including those who are pregnant, postpartum, breastfeeding, or dealing with marked cognitive impairment and complex treatment-resistant depression, require population-specific assessments and often benefit greatly from specialist collaboration. [2-4]

Understanding Why the Initial Decision Point Matters

When a patient remains symptomatic after several weeks of treatment, they might be facing one of several very different clinical problems. The issue could be an inadequate dose or duration, missed doses, poor gastrointestinal absorption, a drug interaction, intolerable adverse effects, an incorrect underlying diagnosis, a medical comorbidity that is sustaining the symptoms, or true inadequate antidepressant efficacy. Treating all of these distinct situations as equivalent can easily lead to premature polypharmacy, repeated ineffective medication switches, or the prolonged continuation of a poorly tolerated regimen. [1-4]

Current guidelines strongly support shared decision-making and allow for several reasonable next steps after an adequate trial. These include dose adjustment, switching medications, adding targeted psychotherapy, or pursuing pharmacologic augmentation. Ultimately, the evidence base does not identify one universal sequence that is best for every single patient. [1-4]

The Primary Care Algorithm at a Glance

Step 0: Pausing the Routine Algorithm for Urgent or Specialty Evaluation

You should arrange a same-day emergency assessment when there is imminent suicide risk, an inability to maintain basic hydration or nutrition, severe self-neglect, psychosis accompanied by unsafe behavior, catatonia, or mania and hypomania with marked functional impairment. Severe depression with psychotic features, catatonia, or a need for a highly rapid response often requires treatments that extend well beyond routine primary care medication management. [3,4]

Early psychiatric consultation is highly recommended for suspected bipolar disorder, recurrent antidepressant-induced activation, diagnostic uncertainty, active substance use that is destabilizing treatment, prominent personality pathology that complicates risk management, pregnancy or perinatal illness, repeated nonadherence despite intervention, severe adverse effects, or a limited capacity to provide the intense monitoring required for certain augmentation strategies. [1-4]

Step 1: Verifying the Diagnosis and the Treatment Trial Before Making Changes

Before labeling a medication as ineffective, it is crucial to document the following clinical factors:

• Diagnosis and course: Confirm a current major depressive episode. Assess previous episodes, and carefully screen for past mania or hypomania, psychosis, trauma-related illness, substance use, complicated grief, and overlapping anxiety disorders. [2-4]
• Safety: Reassess suicidal thoughts, intent, planning, access to lethal means, protective factors, and the level of supervision and follow-up that is realistically available to the patient. [1-4]
• Adherence: Ask openly about missed doses, irregular timing, early discontinuation, affordability issues, refill gaps, and adverse effects that the patient may have been hesitant to volunteer. [1-4]
• Dose and duration: Confirm that the patient actually received a therapeutic dose for at least 4 to 6 weeks. A longer total trial, often 6 to 8 weeks, is entirely reasonable when improvement is actively emerging and adverse effects remain acceptable. [2,3]
• Medical and medication contributors: Review potential physiological barriers such as thyroid disease, anemia, sleep apnea, chronic pain, neurologic illness, and substance use. Evaluate medications that can worsen mood or interfere with treatment, including corticosteroids, sedatives, and hormonal agents. Laboratory testing should be directed by the history, physical examination, and comorbidity profile rather than ordered as an indiscriminate, shotgun panel. [2-4]
• Treatment target: Define remission and functional recovery in terms that are deeply meaningful to the patient, rather than relying solely on a lower symptom score. [1-4]

Step 2: Measuring the Degree of Clinical Improvement

It is best practice to use the same validated scale at baseline and during follow-up. The PHQ-9 is highly practical in primary care, but it should supplement, rather than replace, a thorough clinical interview and direct suicide assessment. A 5-point change on the PHQ-9 is a useful estimate of clinically important within-person improvement. [3,5]

For the sake of making treatment decisions, classify the clinical course pragmatically:

Clinical state	Practical interpretation	Usual next move
Remission or near-remission	Minimal residual symptoms and meaningful functional recovery	Continue the effective dose and plan continuation treatment [1-4]
Partial response	Clear improvement that remains short of response or remission, often approximately 25%-49% symptom reduction	Optimize if the trial is incomplete; otherwise consider augmentation when the base drug is tolerated [2,3]
Minimal or no response	Little meaningful improvement despite an adequate trial	Switch is usually favored, while reassessing diagnosis and adherence [1-4]
Poor tolerability	Adverse effects outweigh benefit, regardless of score change	Reduce dose, switch, or discontinue safely according to the clinical context [1-4]

Keep in mind that a “response” is commonly defined as at least a 50% reduction in symptom severity. True remission requires a low residual symptom burden and a recovery of daily function; a simple percentage improvement alone is rarely enough. [2,3]

Step 3: Choosing Among Optimization, Switching, and Augmentation

Decision	Favors this strategy	Factors that argue against it
Optimize the current antidepressant	Some early improvement, incomplete dose trial, good adherence, acceptable adverse effects	No meaningful benefit after an adequate trial, severe adverse effects, activation, or patient refusal [1-4]
Switch antidepressants	Minimal or no response, poor tolerability, interaction, adherence barrier related to the drug, or preference for monotherapy	A substantial partial response that may be lost during the transition [1-4]
Augment	Partial response, good tolerability, adherence, and a plausible reason to preserve the current antidepressant	No benefit from the base drug, unclear diagnosis, high interaction burden, inadequate monitoring capacity, or patient preference against polypharmacy [1-4]

Option 1: Optimizing the Current Antidepressant Regimen

Dose optimization is a highly reasonable strategy when the patient is tolerating the treatment and has shown early improvement. This is especially true if the trial has not yet reached a fully therapeutic dose or an adequate duration. The CANMAT guidelines note that early improvement by about 4 weeks significantly increases the probability of a later response. Conversely, the absence of early improvement lowers, but does not entirely eliminate, the chance of benefit with continued treatment. [2]

It is important to remember that optimization is not synonymous with automatically increasing the prescription to the maximum possible dose. Higher doses can increase adverse effects and may not add meaningful benefit for every single antidepressant. The decision should carefully account for the drug’s approved dose range, the patient’s age, hepatic and renal function, drug interactions, prior dose-response history, and the overall severity and trajectory of the symptoms. [1-4]

After a dose increase, reassess the patient within 2 to 4 weeks. You should schedule an earlier follow-up when suicide risk, activation, severe adverse effects, or major functional impairment is present. Continue to meticulously document the symptom score, adherence, sleep quality, energy levels, anxiety, daily functioning, suicidal thinking, and any possible manic symptoms. [1-4]

Option 2: Switching to a Different Antidepressant

Switching is usually the cleaner, more straightforward strategy when the initial antidepressant produced little to no benefit, caused clinically important adverse effects, created a problematic drug interaction, caused an adherence problem, or is simply no longer acceptable to the patient. [1-4]

Deciding Between Within-Class and Between-Class Switching

Available evidence does not show reliable overall superiority for switching to a completely different antidepressant class rather than trying another drug within the same class. The next agent should be selected specifically for the individual patient rather than chosen solely to maximize mechanistic novelty. [1-4]

Useful selection factors include prior personal or family response to specific agents, prominent residual symptoms, vulnerability to specific adverse effects, overdose toxicity risks, sexual adverse effects, weight effects, sleep patterns, blood pressure impacts, seizure risk, chronic pain syndromes, drug interactions, pharmacogenetic findings when clinically interpretable, out-of-pocket cost, and formulary access. [1-4]

How to make the transition

There is no universal cross-taper schedule that works for every combination of drugs. A direct switch, a cross-taper, a taper-and-switch, or a taper with a washout period may be appropriate depending on the specific drugs involved, their half-lives, serotonergic activity, interaction profiles, withdrawal risks, and the patient’s current clinical stability. [2-4]

You must avoid abrupt discontinuation when the outgoing antidepressant has clinically important withdrawal potential. Never overlap a monoamine oxidase inhibitor with a contraindicated serotonergic or sympathomimetic drug, and do not improvise washout intervals. Fluoxetine requires special attention because of its exceptionally long half-life. Current product labeling or specialist guidance should always govern high-risk transitions. [2-4]

During a switch, it is vital to distinguish discontinuation symptoms from a true depressive relapse and from the adverse effects of the new medication. Follow up early enough to detect withdrawal, serotonin toxicity, activation, worsening depression, and nonadherence caused by a complicated tapering schedule. [1-4]

Option 3: Augmenting a Partial Response

Augmentation is most rational when the current antidepressant is well tolerated and has produced a meaningful, albeit incomplete, benefit. It is far less rational when the base drug has produced no discernible effect whatsoever. The added treatment should always have a defined target, an expected time to benefit, a clear monitoring plan, and a predefined discontinuation rule. [1-4]

Incorporating Evidence-Based Psychotherapy or Collaborative Care

Augmentation does not automatically mean adding a second medication. Structured psychotherapy and collaborative care models can be seamlessly added to pharmacotherapy. This is particularly effective when residual symptoms are linked to avoidance behaviors, interpersonal stress, chronic insomnia, chronic medical illness, trauma-related patterns, or poor self-management. These non-pharmacologic approaches can also drastically improve medication adherence, systematic follow-up, and access to stepped care. [1,3,4]

Adding Bupropion When Its Clinical Profile Fits the Patient

Bupropion is commonly used off-label as an antidepressant augmentation strategy. In a patient currently taking an SSRI or SNRI, it may be considered when a partial response coexists with fatigue, low drive, or significant concern about sexual adverse effects. However, individual outcomes vary, and its activating effects can sometimes worsen underlying anxiety or insomnia. The VAST-D trial did not show a statistically significant remission advantage for bupropion augmentation over switching to bupropion, but it confirmed that both are reasonable strategies. [2,6,9]

A practical off-label approach is starting bupropion XL at 150 mg each morning, with an increase to 300 mg each morning when clinically appropriate and tolerated. The augmentation indication itself is off-label. Do not use bupropion in patients with a seizure disorder, current or prior bulimia or anorexia nervosa, abrupt discontinuation of alcohol or sedatives, or concomitant monoamine oxidase inhibitor treatment. Monitor blood pressure, insomnia, anxiety, agitation, and overall adherence. [9]

Considering FDA-Labeled Atypical Antipsychotic Adjuncts

Several atypical antipsychotics are FDA-labeled specifically as adjunctive therapy for adult major depressive disorder. The choice should never be reduced to efficacy alone. Akathisia, extrapyramidal symptoms, sedation, orthostasis, weight gain, dyslipidemia, hyperglycemia, drug interactions, cost, and the patient’s ability to complete metabolic monitoring will ultimately determine whether the option is appropriate for their specific life context. [10-15]

Agent	Label-based adult MDD dosing	Practical cautions
Aripiprazole	Start 2-5 mg once daily; labeled range 2-15 mg daily; adjust no more often than weekly	Akathisia, restlessness, insomnia or somnolence, metabolic effects, impulse-control symptoms [10]
Brexpiprazole	Start 0.5 or 1 mg once daily; target 2 mg; maximum 3 mg; increase at weekly intervals	Weight gain, akathisia, somnolence, metabolic effects, orthostasis [11]
Cariprazine	Start 1.5 mg once daily; may increase to 3 mg on day 15; maximum 3 mg daily	Akathisia and other extrapyramidal symptoms, nausea, insomnia; long effective half-life delays full assessment of dose changes [12]
Lumateperone	42 mg once daily with or without food; no titration needed; reduce to 21 mg with a moderate CYP3A4 inhibitor or moderate/severe hepatic impairment and to 10.5 mg with a strong CYP3A4 inhibitor	Dizziness, dry mouth, somnolence or sedation, nausea, fatigue, diarrhea; avoid CYP3A4 inducers [13,14]
Quetiapine XR	Start 50 mg in the evening; increase to 150 mg on day 3; labeled adjunctive range 150-300 mg daily	Sedation, orthostasis, weight and metabolic effects; dose-related tolerability burden [15]

Lumateperone’s adult MDD adjunctive indication was added to U.S. labeling in November 2025. Its approval was based on two 6-week placebo-controlled trials in adults with inadequate response to one or two antidepressant courses. While it expands the labeled options, it has not established a universally preferred position over older adjuncts. [13,14]

All antipsychotics in this context require a thorough discussion of boxed warnings. This includes the increased mortality risk in older adults with dementia-related psychosis and the antidepressant-class warning about suicidal thoughts and behaviors in pediatric and young adult patients. These drugs are not approved to treat dementia-related psychosis. [10-16]

Before starting an atypical antipsychotic, document weight or body mass index, blood pressure, glycemic status, lipid profile, movement symptoms, and relevant cardiovascular or fall risk. Repeat weight and adverse-effect assessments early, and repeat metabolic laboratory testing according to the specific agent, baseline risk, and current guidance. Ask directly about akathisia, restlessness, sedation, orthostasis, abnormal movements, impulse-control symptoms, and worsening suicidal thinking. [4,10-16]

Reserving the Olanzapine-Fluoxetine Combination for Selected Treatment-Resistant Cases

The fixed olanzapine-fluoxetine combination is FDA-labeled for treatment-resistant depression in adults. The label defines this as a failure to respond to two separate antidepressants of adequate dose and duration in the current episode. The usual adult starting dose is olanzapine 6 mg with fluoxetine 25 mg in the evening, with individualized dosing within the labeled range. Its significant metabolic and sedative burden makes it a higher-complexity option that often fits better in a psychiatric or shared-care setting. [16]

Avoiding Mirtazapine Add-On Therapy as a Reflexive Default

The MIR primary care trial found no clinically important benefit from routinely adding mirtazapine to an SSRI or SNRI for treatment-resistant depression. Furthermore, the trial found more adverse effects and higher rates of treatment discontinuation. Mirtazapine may still be selected for an individual patient when its specific sleep, appetite, or tolerability profile is highly desired, but the trial data simply does not support routine add-on use just because the first antidepressant produced an incomplete response. [8]

Managing Lithium and Triiodothyronine Augmentation with Specialist Support

Lithium and triiodothyronine both have solid evidence as augmentation strategies. However, their evidence base, off-label status for this specific use, interaction burden, toxicity risk, and intense monitoring requirements make them less suitable as routine, unsupported primary care additions. Lithium requires renal, thyroid, calcium, serum level, interaction, hydration, and toxicity monitoring. These strategies are generally best initiated with psychiatric consultation or a clearly defined shared-care protocol. [2,4]

Insights From Comparative Trials Like VAST-D and OPTIMUM

The VAST-D trial enrolled 1,522 patients whose depression had not responded adequately to an initial antidepressant. At 12 weeks, remission occurred in 22.3% of patients after switching to bupropion, 26.9% with bupropion augmentation, and 28.9% with aripiprazole augmentation. While aripiprazole augmentation was statistically superior to switching, the absolute difference was modest. Additionally, 85.2% of the participants were men, predominantly veterans. The trial supports aripiprazole as a highly reasonable option, but not as a mandatory next step for every primary care patient. [6]

The OPTIMUM trial studied adults aged 60 years or older with treatment-resistant depression. In the first step, remission occurred in 28.9% of patients with aripiprazole augmentation, 28.2% with bupropion augmentation, and 19.3% after switching to bupropion. Notably, bupropion augmentation had the highest rate of falls. Because the trial was open-label and focused exclusively on older adults, it is most useful for geriatric decision-making rather than for establishing a universal sequence for all adults. [7]

Together, these trials reinforce a broader clinical point: the average remission differences among reasonable next-step options are often much smaller than the differences in tolerability, safety, monitoring burden, and patient acceptability for an individual person. [6,7]

Structuring Follow-Up Care After Any Medication Change

Schedule a follow-up appointment within 2 to 4 weeks after starting, increasing, switching, or augmenting a medication. You should use a shorter interval, telephone contact, or a same-week review when suicide risk, severe symptoms, activation, withdrawal, complex cross-tapering, or major adverse effects are present. During acute treatment changes, at least monthly measurement-based follow-up should continue until the patient is completely stable or in full remission. [1-4]

At each visit, be sure to assess:

• The PHQ-9 or another consistent symptom measure, paired with a direct clinical interview. [3,5]
• Suicidal thoughts, intent, behavior, access to lethal means, and protective factors. [1-4]
• Adherence, refill access, schedule complexity, and substance use. [1-4]
• Sleep quality, energy, anxiety, cognition, sexual function, weight, appetite, and occupational or social functioning. [1-4]
• Signs of activation, decreased need for sleep, impulsivity, unusual goal-directed behavior, psychosis, or other evidence of bipolarity. [2-4]
• Drug-specific adverse effects, interactions, vital signs, laboratory monitoring parameters, and movement symptoms. [4,9-16]

It is vital to define in advance what will count as success. A medication should never be continued indefinitely as an augmentation agent when there is no meaningful symptomatic or functional benefit. When benefit is achieved, document which component appears useful, the planned duration of therapy, and how future deprescribing will be considered. [1-4]

Special Considerations for Older Adults and Higher-Risk Populations

In older adults, it is best to start lower when appropriate, titrate more slowly, and rigorously review orthostasis, fall risk, anticholinergic burden, hyponatremia risk, cognition, renal and hepatic function, and drug interactions. Sedating or activating effects may have far greater functional consequences in the elderly than in younger adults. The OPTIMUM trial suggests that aripiprazole and bupropion augmentation can be effective in later life, but the fall signal associated with bupropion augmentation and the general adverse-effect burden of antipsychotics require highly individualized assessment. [7,10-16]

For adults aged 18 to 24 years, you must discuss the boxed warning regarding the increased risk of suicidal thoughts and behaviors during antidepressant treatment and monitor them closely during initiation and dose changes. The presence of suicidal ideation does not automatically contraindicate antidepressant treatment, but it drastically changes the required intensity of risk assessment, follow-up, safety planning, and escalation protocols. [9-16]

Patients navigating pregnancy, postpartum illness, breastfeeding, severe hepatic or renal impairment, seizure risk, eating disorders, dementia, significant cardiovascular disease, or multiple interacting medications need population-specific and drug-specific decisions that frequently fall outside the scope of a general primary care algorithm. [2-4,9-16]

Determining When to Refer or Co-Manage with Psychiatry

Psychiatric consultation is highly appropriate after two adequate antidepressant trials have failed to produce remission. It is also appropriate much earlier when the diagnosis is uncertain or the proposed strategy exceeds the practice’s monitoring capacity. Do not wait for two failures when the patient is exhibiting psychosis, catatonia, mania or hypomania, escalating suicide risk, severe functional collapse, intolerable treatment complications, or a need for rapid or advanced intervention. [1-4]

Referral does not require abandoning your primary care involvement. Collaborative care models can beautifully preserve continuity for medical comorbidities, adherence counseling, laboratory monitoring, safety planning, and long-term maintenance while a psychiatrist guides the more complex pharmacotherapy. [1,3,4]

Acknowledging the Limitations of the Current Evidence Base

Major guidelines generally agree on the need for measurement-based reassessment and shared decision-making, but they often differ in how they rank individual adjuncts. Many recommendations made after an inadequate response are conditional simply because direct comparative evidence remains limited. [1-4]

The VAST-D trial primarily enrolled male veterans, the OPTIMUM trial focused exclusively on adults aged 60 years or older and utilized an open-label design, and many antipsychotic adjunctive trials lasted only about 6 weeks. Long-term comparative data on remission durability, daily functioning, metabolic harm, withdrawal syndromes, and deprescribing remain frustratingly limited. [6,7,10-16]

Furthermore, newer regulatory options should not be mistaken for proven clinical superiority. Lumateperone adds a welcome labeled choice, but its relative place among aripiprazole, brexpiprazole, cariprazine, quetiapine XR, non-antipsychotic augmentation, and switching will require longer-term and head-to-head evidence to fully define. [13,14]

The Practical Bottom Line for Primary Care Practice

After an initial antidepressant fails to produce remission, first verify the diagnosis, safety, adherence, dose, duration, interactions, and comorbidities. Then, make the treatment decision according to the specific pattern of benefit and tolerability:

1. Optimize when improvement is emerging and the current drug is well tolerated.
2. Switch when the response is absent or minimal, adverse effects are limiting, or monotherapy is strongly preferred.
3. Augment when a meaningful partial response is worth preserving and adequate monitoring is feasible.
4. Refer or co-manage when two adequate trials have failed, the diagnosis is uncertain, safety risk is elevated, or the next intervention exceeds primary care capacity. [1-4]

The algorithm succeeds when it produces a documented, time-limited plan with a measurable target, not when it merely adds another medication to the patient’s list. Remission, functional recovery, safety, and patient preference remain the endpoints that truly matter. [1-4]

References

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2. Lam RW, Kennedy SH, Adams C, et al. Canadian Network for Mood and Anxiety Treatments (CANMAT) 2023 Update on Clinical Guidelines for Management of Major Depressive Disorder in Adults. Can J Psychiatry. 2024;69(9):641-687. https://doi.org/10.1177/07067437241245384 PMID: 38711351.

3. Department of Veterans Affairs, Department of Defense. VA/DoD Clinical Practice Guideline for the Management of Major Depressive Disorder. Version 4.0. February 2022. https://www.healthquality.va.gov/guidelines/MH/mdd/ Accessed August 12, 2026.

4. National Institute for Health and Care Excellence. Depression in adults: treatment and management. NICE guideline NG222. June 29, 2022. https://www.nice.org.uk/guidance/ng222 Accessed August 12, 2026.

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6. Mohamed S, Johnson GR, Chen P, et al. Effect of Antidepressant Switching vs Augmentation on Remission Among Patients With Major Depressive Disorder Unresponsive to Antidepressant Treatment: The VAST-D Randomized Clinical Trial. JAMA. 2017;318(2):132-145. https://doi.org/10.1001/jama.2017.8036 PMID: 28697253.

7. Lenze EJ, Mulsant BH, Roose SP, et al. Antidepressant Augmentation versus Switch in Treatment-Resistant Geriatric Depression. N Engl J Med. 2023;388(12):1067-1079. https://doi.org/10.1056/NEJMoa2204462 PMID: 36867173.

8. Kessler DS, MacNeill SJ, Tallon D, et al. Mirtazapine added to SSRIs or SNRIs for treatment resistant depression in primary care: phase III randomised placebo controlled trial (MIR). BMJ. 2018;363. https://doi.org/10.1136/bmj.k4218 PMID: 30381374.

9. DailyMed. Bupropion hydrochloride extended-release tablets (XL), prescribing information. https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=1724f474-d6ab-46af-940f-7f874d4ff7fc Accessed August 12, 2026.

10. DailyMed. Aripiprazole tablets, prescribing information. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=85cc7d25-414b-4b6f-a03a-48af908a16a1 Accessed August 12, 2026.

11. DailyMed. Brexpiprazole tablets, prescribing information. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=993b584c-7fe6-4551-899f-39146c8508ac Accessed August 12, 2026.

12. DailyMed. VRAYLAR (cariprazine) capsules, prescribing information. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=4b5f7c65-aa2d-452a-b3db-bc85c06ff12f Accessed August 12, 2026.

13. DailyMed. CAPLYTA (lumateperone) capsules, prescribing information. Revised April 2026. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=db730b06-6351-47fd-8183-e61e61bbead5 Accessed August 12, 2026.

14. Durgam S, Earley WR, Kozauer SG, et al. Lumateperone adjunctive therapy in patients with major depressive disorder: results from a randomized, double-blind, placebo-controlled phase 3 study. J Clin Psychiatry. 2025;86(4):25m15848. https://doi.org/10.4088/JCP.25m15848 PMID: 40875502.

15. DailyMed. SEROQUEL XR (quetiapine fumarate extended-release) tablets, prescribing information. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=2a74e8a0-b2fd-4d7f-8bf8-72148b1d3ae7 Accessed August 12, 2026.

16. DailyMed. Olanzapine and fluoxetine capsules, prescribing information. Revised March 2026. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=3c28cf18-01a3-468a-ab3e-8aa82f918251 Accessed August 12, 2026.