REMERON SOLTAB

Clinical safety rating: caution

Comprehensive clinical and safety monograph for REMERON SOLTAB (REMERON SOLTAB).

How it works

Mirtazapine is a tetracyclic antidepressant that acts as an antagonist at presynaptic α2-adrenergic autoreceptors and heteroreceptors, enhancing norepinephrine and serotonin release. It also antagonizes 5-HT2 and 5-HT3 receptors, and H1 and α1 receptors.

What the body does with it

Metabolism	Extensively metabolized in the liver via CYP1A2, CYP2D6, and CYP3A4; also undergoes glucuronidation. Major metabolites include desmethylmirtazapine and mirtazapine N-oxide.
Excretion	Renal: 75% (mostly as glucuronide conjugates, with 8-15% unchanged); Fecal: 15%; Biliary: minor.
Half-life	20-40 hours (mean 30 hours); prolonged in elderly (up to 60 hours) and hepatic impairment.
Protein binding	85% bound to alpha-1-acid glycoprotein and albumin.
Volume of Distribution	10-20 L/kg (large, indicating extensive tissue distribution).
Bioavailability	Oral: 50% (due to first-pass metabolism); SolTab bioequivalent to tablet.
Onset of Action	Oral (including SolTab): 2-4 weeks for antidepressant effect; sedative effects within 1-2 hours.
Duration of Action	24 hours (once-daily dosing); clinical effect sustained with regular use.

Classification & Brands

Dosing & administration

15 to 45 mg orally once daily at bedtime, typically starting at 15 mg/day.

Dosage form	TABLET, ORALLY DISINTEGRATING
Renal impairment	No specific dosage adjustment required for mild to moderate renal impairment. For severe renal impairment (eGFR < 30 mL/min/1.73 m²), use with caution and consider reducing dose, as clearance may be decreased.
Liver impairment	Child-Pugh Class A and B: No specific adjustment; use with caution. Child-Pugh Class C: Contraindicated due to reduced metabolism and increased risk of toxicity.
Pediatric use	Not FDA-approved for pediatric use; limited data available. In adolescents (12-17 years) for major depressive disorder, dosing may be initiated at 15 mg/day and titrated; however, safety and efficacy not established. Weight-based dosing not routinely recommended.
Geriatric use	Use lower initial dose (7.5 mg/day) and titrate slowly; clearance reduced in elderly. Monitor for sedation, orthostatic hypotension, and anticholinergic effects.

Use during pregnancy

1st trimester	Consult provider
2nd trimester	Consult provider
3rd trimester	Consult provider

Clinical note

Comprehensive clinical and safety monograph for REMERON SOLTAB (REMERON SOLTAB).

Breastfeeding	Mirtazapine is excreted into breast milk; relative infant dose approximately 1-2% of maternal weight-adjusted dose, M/P ratio about 1.1. Limited data show no adverse effects in breastfed infants, but monitor for sedation. Generally considered compatible with breastfeeding.
Teratogenic Risk	First trimester: Limited data, no conclusive human teratogenicity; animal studies show no major malformations at clinically relevant doses. Second/third trimester: Risk of persistent pulmonary hypertension of the newborn (PPHN) and neonatal withdrawal syndrome (irritability, feeding difficulties, respiratory distress).

Warnings & precautions

■ FDA Black Box Warning

Increased risk of suicidal thinking and behavior in children, adolescents, and young adults with major depressive disorder and other psychiatric disorders.

Side Effect Profile

Serious Effects

Absolute Contraindications

["Hypersensitivity to mirtazapine or any excipient","Concomitant use or within 14 days of MAOIs (risk of serotonin syndrome)","Severe hepatic impairment (Child-Pugh class C)"]

Clinical Precautions

Precautions

["Agranulocytosis (rare but serious; monitor for symptoms like fever, sore throat)","Serotonin syndrome (risk with concomitant serotonergic drugs)","Increased cholesterol and triglycerides","Sedation (may impair ability to drive or operate machinery)","Hyponatremia (especially in elderly or volume-depleted patients)","Activation of mania/hypomania in bipolar patients","QT prolongation (caution with electrolyte disturbances, concurrent QT-prolonging drugs)","Dizziness and orthostatic hypotension"]

Clinical Tips & Counseling

Drug interactions

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REMERON SOLTAB

Clinical safety rating: caution

Comprehensive clinical and safety monograph for REMERON SOLTAB (REMERON SOLTAB).

How it works

What the body does with it

Metabolism	Extensively metabolized in the liver via CYP1A2, CYP2D6, and CYP3A4; also undergoes glucuronidation. Major metabolites include desmethylmirtazapine and mirtazapine N-oxide.
Excretion	Renal: 75% (mostly as glucuronide conjugates, with 8-15% unchanged); Fecal: 15%; Biliary: minor.
Half-life	20-40 hours (mean 30 hours); prolonged in elderly (up to 60 hours) and hepatic impairment.
Protein binding	85% bound to alpha-1-acid glycoprotein and albumin.
Volume of Distribution	10-20 L/kg (large, indicating extensive tissue distribution).
Bioavailability	Oral: 50% (due to first-pass metabolism); SolTab bioequivalent to tablet.
Onset of Action	Oral (including SolTab): 2-4 weeks for antidepressant effect; sedative effects within 1-2 hours.
Duration of Action	24 hours (once-daily dosing); clinical effect sustained with regular use.

Classification & Brands

Dosing & administration

15 to 45 mg orally once daily at bedtime, typically starting at 15 mg/day.

Dosage form	TABLET, ORALLY DISINTEGRATING
Renal impairment	No specific dosage adjustment required for mild to moderate renal impairment. For severe renal impairment (eGFR < 30 mL/min/1.73 m²), use with caution and consider reducing dose, as clearance may be decreased.
Liver impairment	Child-Pugh Class A and B: No specific adjustment; use with caution. Child-Pugh Class C: Contraindicated due to reduced metabolism and increased risk of toxicity.
Pediatric use	Not FDA-approved for pediatric use; limited data available. In adolescents (12-17 years) for major depressive disorder, dosing may be initiated at 15 mg/day and titrated; however, safety and efficacy not established. Weight-based dosing not routinely recommended.
Geriatric use	Use lower initial dose (7.5 mg/day) and titrate slowly; clearance reduced in elderly. Monitor for sedation, orthostatic hypotension, and anticholinergic effects.

Use during pregnancy

1st trimester	Consult provider
2nd trimester	Consult provider
3rd trimester	Consult provider

Clinical note

Comprehensive clinical and safety monograph for REMERON SOLTAB (REMERON SOLTAB).

Breastfeeding	Mirtazapine is excreted into breast milk; relative infant dose approximately 1-2% of maternal weight-adjusted dose, M/P ratio about 1.1. Limited data show no adverse effects in breastfed infants, but monitor for sedation. Generally considered compatible with breastfeeding.
Teratogenic Risk	First trimester: Limited data, no conclusive human teratogenicity; animal studies show no major malformations at clinically relevant doses. Second/third trimester: Risk of persistent pulmonary hypertension of the newborn (PPHN) and neonatal withdrawal syndrome (irritability, feeding difficulties, respiratory distress).

Warnings & precautions

■ FDA Black Box Warning

Increased risk of suicidal thinking and behavior in children, adolescents, and young adults with major depressive disorder and other psychiatric disorders.

Side Effect Profile

Serious Effects

Absolute Contraindications

["Hypersensitivity to mirtazapine or any excipient","Concomitant use or within 14 days of MAOIs (risk of serotonin syndrome)","Severe hepatic impairment (Child-Pugh class C)"]