Two medicines, side by side
Mirtazapine vs olanzapine
Mirtazapine and olanzapine are both labeled for depression. Drugs@FDA records approvals of mirtazapine since 1996 and of olanzapine since 1996. Pharmacies paid $0.063 per mirtazapine 15 mg tablet and $0.147 per olanzapine 20 mg tablet (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like.
Check it at the source: the mirtazapine FDA label on DailyMed (effective August 6, 2025); the olanzapine FDA label on DailyMed (effective March 5, 2026).
Highlights of the mirtazapine record
Mirtazapine (Remeron) · label of August 6, 2025
SUICIDAL THOUGHTS AND BEHAVIORS Antidepressants increased the risk of suicidal thoughts and behaviors in pediatric and young adult patients in short-term studies. Closely monitor all antidepressant-treated patients for clinical worsening, and for emergence of suicidal thoughts and behaviors [see Warnings and Precautions (5.1) ]. REMERON/REMERONSolTab is not approved for use in pediatric patients [see Use in Specific Populations (8.4) ].
Used for
From the label: indicationsREMERON/REMERONSolTab are indicated for the treatment of major depressive disorder (MDD) in adults [see Clinical Studies (14) ]. REMERON/REMERONSolTab is indicated for the treatment of major depressive disorder (MDD) in adults.
On the market
- Earliest approval on file
- June 14, 1996
- Generic labelers
- 36 labelers
- Pharmacy cost
- $0.063 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 5
Highlights of the olanzapine record
Olanzapine (Zyprexa) · label of March 5, 2026
INCREASED MORTALITY IN ELDERLY PATIENTS WITH DEMENTIA-RELATED PSYCHOSIS Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. Analyses of seventeen placebo-controlled trials (modal duration of 10 weeks), largely in patients taking atypical antipsychotic drugs, revealed a risk of death in drug-treated patients of between 1.6 to 1.7 times the risk of death in placebo-treated patients.
Used for
From the label: indicationsOlanzapine is an atypical antipsychotic indicated: As oral formulation for the: · Treatment of schizophrenia. ( 1.1 ) · Adults: Efficacy was established in three clinical trials in patients with schizophrenia: two 6-week trials and one maintenance trial. ( 14.1 ) · Adolescents (ages 13-17): Efficacy was established in one 6-week trial in patients with schizophrenia ( 14.1 ). […]
On the market
- Earliest approval on file
- September 30, 1996
- Generic labelers
- 43 labelers
- Pharmacy cost
- $0.147 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 14
Source: FDA drug labels via openFDA (Mirtazapine label of August 6, 2025, Olanzapine label of March 5, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do mirtazapine and olanzapine differ on the record?
How each works, in its label's words: Mirtazapine, “The mechanism of action of mirtazapine for the treatment of major depressive disorder, is unclear.”; Olanzapine, “The mechanism of action of olanzapine, in the listed indications is unclear.”
Half-life, in each label's words: Mirtazapine, “Elimination Mirtazapine has a half-life of about 20 to 40 hours following oral administration of REMERON or …”; Olanzapine, “Its half-life ranges from 21 to 54 hours (5th to 95th percentile; mean of 30 hr), and apparent plasma clearance ranges …”
Both labels carry a boxed warning; the records quote them.
Generics: mirtazapine since 2003; olanzapine since 2011 (Drugs@FDA).
| Mirtazapine | Olanzapine | |
|---|---|---|
| Labeled for | Depression | Schizophrenia, Bipolar disorder, Depression |
| Pharmacologic class | n/a | Atypical Antipsychotic |
| How it works (label) | The mechanism of action of mirtazapine for the treatment of major depressive disorder, is unclear. | The mechanism of action of olanzapine, in the listed indications is unclear. However, the efficacy of olanzapine in schizophrenia could be mediated through a combination of dopamine and serotonin type 2 (5HT 2 ) antagonism. |
| Half-life (label) | Elimination Mirtazapine has a half-life of about 20 to 40 hours following oral administration of REMERON or REMERONSolTab. | Its half-life ranges from 21 to 54 hours (5th to 95th percentile; mean of 30 hr), and apparent plasma clearance ranges from 12 to 47 L/hr (5th to 95th percentile; mean of 25 L/hr). |
| Earliest approval on file (Drugs@FDA) | June 14, 1996 | September 30, 1996 |
| First generic approved | January 24, 2003 | October 24, 2011 |
| Generic labelers (NDC) | 36 labelers | 43 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.063 per tablet (Mirtazapine 15 mg tablet) | $0.147 per tablet (Olanzapine 20 mg tablet) |
| 12-month price change | -12% | -5% |
| Boxed warning | Yes | Yes |
| Shortage now | No current entry | No current entry |
| Recalls recorded | 5 | 14 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 91,057 | 107,881 |
| DEA schedule | none | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
What do the labels say about using others of their kind?
Mirtazapine label, warnings and precautionsIncreased risk when co-administered with other serotonergic drugs (e.g., SSRI, SNRI, triptans), but also when taken alone.
Source: FDA drug labels via openFDA
What next?
- Alternatives to mirtazapine
- every medicine labeled for the same conditions