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Registry Hub
Peer-Reviewed Evidence
HomeDrug RegistryCompareINVEGA TRINZA vs TRAZODONE HYDROCHLORIDE
Comparative Pharmacology

INVEGA TRINZA vs TRAZODONE HYDROCHLORIDE Comparison

Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.

Clinical EssentialsPharmacokineticsSpecial PopulationsSafety & MonitoringPregnancy & LactationClinical Insights
Differential Analysis

INVEGA TRINZA vs TRAZODONE HYDROCHLORIDE

Head-to-head clinical comparison of therapeutic indices and safety profiles.

View INVEGA TRINZA Monograph View TRAZODONE HYDROCHLORIDE Monograph
INVEGA TRINZA
Atypical Antipsychotic
Category C
TRAZODONE HYDROCHLORIDE
Serotonin Antagonist and Reuptake Inhibitor (SARI)
Category A/B

Clinical Essentials

INVEGA TRINZA
TRAZODONE HYDROCHLORIDE
Mechanism of Action
INVEGA TRINZA

Paliperidone is the major active metabolite of risperidone. It is a benzisoxazole derivative antipsychotic that antagonizes central dopamine type 2 (D2) and serotonin type 2 (5-HT2A) receptors. It also antagonizes alpha-1 and alpha-2 adrenergic, and histamine H1 receptors.

TRAZODONE HYDROCHLORIDE

Trazodone hydrochloride is a triazolopyridine derivative with antidepressant activity. Its mechanism of action is not fully understood, but it is believed to involve inhibition of serotonin reuptake and antagonism at 5-HT2A and 5-HT2C receptors, as well as antagonism at alpha1-adrenergic and histamine H1 receptors.

Indications
INVEGA TRINZA

Schizophrenia (FDA-approved maintenance treatment in patients adequately treated with once-monthly paliperidone palmitate for at least 4 months)

TRAZODONE HYDROCHLORIDE

Major Depressive Disorder (MDD),Insomnia (off-label),Anxiety disorders (off-label),Fibromyalgia (off-label),Neuropathic pain (off-label),Bulimia nervosa (off-label)

Standard Dosing
INVEGA TRINZA

Administered intramuscularly (gluteal or deltoid) at 3-month intervals. Starting dose: 350 mg, 525 mg, or 700 mg based on prior stabilization dose of oral paliperidone or INVEGA SUSTENNA. Maximum dose: 700 mg.

TRAZODONE HYDROCHLORIDE

Initial 150 mg/day orally in divided doses, may increase by 50 mg/day every 3-4 days; usual range 150-400 mg/day; maximum 600 mg/day for inpatients.

Direct Interaction
INVEGA TRINZA
No Direct Interaction
TRAZODONE HYDROCHLORIDE
No Direct Interaction

Pharmacokinetics

INVEGA TRINZA
TRAZODONE HYDROCHLORIDE
Half-Life
INVEGA TRINZA

Terminal elimination half-life: 3 to 6 months (mean 118 days) due to slow dissolution from intramuscular depot; clinical context: steady state reached after 3 injections every 3 months.

TRAZODONE HYDROCHLORIDE

5-9 hours (biphasic: alpha phase 3-6 min, beta phase 5-9 h); prolonged in elderly and hepatic impairment

Metabolism
INVEGA TRINZA

Paliperidone is predominantly metabolized by dealkylation, hydroxylation, and dehydrogenation, with minor contribution from CYP2D6 and CYP3A4. It is also a substrate of P-glycoprotein (P-gp).

Special Populations

INVEGA TRINZA
TRAZODONE HYDROCHLORIDE
Renal Adjustments
INVEGA TRINZA

Contraindicated in e GFR <15 m L/min/1.73m². For e GFR 15-29 m L/min/1.73m²: 350 mg initially, then 350 mg every 3 months. For e GFR 30-49 m L/min/1.73m²: 350 mg initially, then 350 mg every 3 months. For e GFR ≥50 m L/min/1.73m²: no adjustment.

TRAZODONE HYDROCHLORIDE

e GFR <30 m L/min: Use with caution; consider starting at 25-50 mg/day and titrate slowly. No specific dose reduction for mild-moderate impairment.

Hepatic Adjustments

Safety & Monitoring

INVEGA TRINZA
TRAZODONE HYDROCHLORIDE
Black Box Warnings
INVEGA TRINZA
FDA Black Box Warning

Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. INVEGA TRINZA is not approved for use in patients with dementia-related psychosis.

Pregnancy & Lactation

INVEGA TRINZA
TRAZODONE HYDROCHLORIDE
Teratogenic Risk
INVEGA TRINZA

INVEGA TRINZA (paliperidone palmitate) is a Pregnancy Category C drug. First trimester: Limited human data; animal studies show increased fetal resorptions and skeletal delays at high doses. Second and third trimesters: Risk for extrapyramidal and withdrawal symptoms in neonates after in utero exposure (e.g., agitation, hypertonia, hypotonia, tremor, somnolence, respiratory distress). Antipsychotic use near term may increase risk for neonatal extrapyramidal symptoms. Overall, risk-benefit analysis required.

TRAZODONE HYDROCHLORIDE

Pregnancy Category C. First trimester: Associated with a small increased risk of congenital malformations, particularly cardiac defects, based on some observational studies. Second and third trimesters: Risk of persistent pulmonary hypertension of the newborn (PPHN) and neonatal withdrawal syndrome including respiratory distress, jitteriness, and feeding difficulties if used near term.

Clinical Insights

INVEGA TRINZA
TRAZODONE HYDROCHLORIDE
Clinical Pearls
INVEGA TRINZA

INVEGA TRINZA is a long-acting injectable paliperidone palmitate formulation administered every 3 months. It requires 2 loading doses of the monthly formulation (INVEGA SUSTENNA) prior to initiation. The dose should be adjusted based on renal function, and it is contraindicated in patients with severe renal impairment (e GFR < 15 m L/min/1.73m2). Administer only intramuscularly into the deltoid or gluteal muscle; do not administer intravenously or subcutaneously. Use with caution in patients with known risk factors for QT prolongation, significant leukocyte/neutrophil count abnormalities, or a history of neuroleptic malignant syndrome. Monitor for orthostatic hypotension, especially during dose titration.

TRAZODONE HYDROCHLORIDE

Trazodone is associated with priapism; instruct patients to seek emergency care if erection persists >4 hours. It also carries a risk of serotonin syndrome, especially when co-administered with other serotonergic drugs. The sedative effect is often used off-label for insomnia. QT prolongation risk is dose-dependent; monitor ECG in elderly or those with cardiac disease. Start at low doses (25-50 mg at bedtime) to minimize orthostatic hypotension and sedation. Use with caution in patients with recent myocardial infarction or unstable heart disease.

Safety Verification

Known Interactions

INVEGA TRINZA Risks

No interactions on record

TRAZODONE HYDROCHLORIDE Risks

No interactions on record

Clinical Q&A

Frequently Asked Questions

1. What is the primary difference between INVEGA TRINZA and TRAZODONE HYDROCHLORIDE?

INVEGA TRINZA and TRAZODONE HYDROCHLORIDE are distinct pharmacological agents. INVEGA TRINZA belongs to the Atypical Antipsychotic class and is primarily used for Schizophrenia (FDA-approved maintenance treatment in patients adequately treated with once-monthly paliperidone palmitate for at least 4 months). TRAZODONE HYDROCHLORIDE belongs to the Serotonin Antagonist and Reuptake Inhibitor (SARI) class and is primarily used for Major Depressive Disorder (MDD)Insomnia (off-label)Anxiety disorders (off-label)Fibromyalgia (off-label)Neuropathic pain (off-label)Bulimia nervosa (off-label). Their specific mechanisms of action, pharmacokinetic characteristics, and side effects differ.

2. Are INVEGA TRINZA and TRAZODONE HYDROCHLORIDE safe during pregnancy?

The maternal-fetal safety profiles of these drugs differ. INVEGA TRINZA carries a safety status of Category C, whereas TRAZODONE HYDROCHLORIDE safety is classified as Category A/B. Consult a board-certified physician or healthcare specialist to establish an accurate, individualized pregnancy risk assessment before starting either therapy.

TRAZODONE HYDROCHLORIDE

Primarily hepatic via CYP3A4 to active metabolite meta-chlorophenylpiperazine (m-CPP). Also via CYP2D6 and CYP1A2. m-CPP is further metabolized by CYP2D6. Trazodone and m-CPP are also substrates for P-glycoprotein.

Excretion
INVEGA TRINZA

Renal: 59-80% as unchanged drug and metabolites; fecal: 6-15%; biliary: minimal.

TRAZODONE HYDROCHLORIDE

Renal (70-75% as metabolites, <1% as parent drug); fecal (20-25%); biliary (minor)

Protein Binding
INVEGA TRINZA

74-84% bound to albumin and alpha-1-acid glycoprotein.

TRAZODONE HYDROCHLORIDE

89-95% bound to albumin

VD (L/kg)
INVEGA TRINZA

Vd: 2-4 L/kg (extensive tissue distribution); clinical meaning: high Vd indicates extensive peripheral binding, supporting long duration.

TRAZODONE HYDROCHLORIDE

0.8-1.5 L/kg (extensive distribution into tissues)

Bioavailability
INVEGA TRINZA

Intramuscular: 100% (absolute bioavailability after injection).

TRAZODONE HYDROCHLORIDE

Oral: ~65% (variable due to first-pass metabolism)

INVEGA TRINZA

No dose adjustment required for mild to moderate hepatic impairment (Child-Pugh Class A and B). Not studied in severe impairment (Child-Pugh Class C).

TRAZODONE HYDROCHLORIDE

Child-Pugh Class B or C: Reduce dose by 50% and titrate cautiously; contraindicated in severe hepatic impairment (Child-Pugh Class C) due to risk of hepatic encephalopathy.

Pediatric Dosing
INVEGA TRINZA

Not approved for use in pediatric patients. Safety and efficacy not established in patients <18 years.

TRAZODONE HYDROCHLORIDE

Not approved for use in children <18 years; limited data for depression: 1-2 mg/kg/day orally in divided doses, max 6 mg/kg/day or 400 mg/day.

Geriatric Dosing
INVEGA TRINZA

No specific dose adjustment recommended, but elderly patients may have reduced renal function; assess renal function (e GFR) and adjust accordingly. Use lowest effective dose and monitor for orthostatic hypotension, sedation, and extrapyramidal symptoms.

TRAZODONE HYDROCHLORIDE

Initial dose 25-50 mg/day orally; increase slowly by 25-50 mg every 3-4 days; maximum 300 mg/day.

TRAZODONE HYDROCHLORIDE
FDA Black Box Warning

WARNING: SUICIDAL THOUGHTS AND BEHAVIORS - Antidepressants increased the risk of suicidal thoughts and behavior in children, adolescents, and young adults in short-term studies. Closely monitor for worsening and emergence of suicidal thoughts and behaviors.

Warnings/Precautions
INVEGA TRINZA
  • Increased mortality in elderly patients with dementia-related psychosis
  • Cerebrovascular adverse events (e.g., stroke, transient ischemic attack) in elderly patients with dementia-related psychosis
  • Neuroleptic malignant syndrome (NMS)
  • Tardive dyskinesia (TD)
  • Metabolic changes (hyperglycemia, diabetes mellitus, dyslipidemia, weight gain)
  • Hyperprolactinemia
  • Orthostatic hypotension and syncope
  • Leukopenia, neutropenia, and agranulocytosis
  • Seizures
  • Potential for cognitive and motor impairment
  • Dysphagia
  • Priapism
  • Body temperature regulation disruption
  • Suicide risk
  • Administration errors (not interchangeable with other formulations of paliperidone)
TRAZODONE HYDROCHLORIDE
  • Suicidal thoughts and behaviors (monitor closely)
  • Serotonin syndrome (risk when co-administered with other serotonergic drugs)
  • Priapism (urgent intervention required)
  • Orthostatic hypotension and syncope (especially in patients with cardiovascular disease)
  • QT interval prolongation (risk increased with dose >300 mg/day or in patients with risk factors)
  • Activation of mania/hypomania (screen for bipolar disorder)
  • Angle-closure glaucoma (may cause mydriasis)
  • Hyponatremia (SIADH reported)
  • Use in patients with hepatic or renal impairment (caution advised)
Contraindications
INVEGA TRINZA
  • Hypersensitivity to paliperidone, risperidone, or any component of the formulation
TRAZODONE HYDROCHLORIDE
  • Concomitant use of MAOIs or within 14 days of MAOI discontinuation
  • Concomitant use of linezolid or intravenous methylene blue
  • Hypersensitivity to trazodone or any component of the formulation
  • QT interval prolongation (congenital or acquired) or use with drugs that prolong QT interval
Adverse Reactions
INVEGA TRINZA
Data Pending
TRAZODONE HYDROCHLORIDE
Data Pending
Food Interactions
INVEGA TRINZA

Avoid grapefruit juice as it may increase paliperidone levels. No significant food interactions otherwise. Advise moderation of alcohol as it may exacerbate CNS depression.

TRAZODONE HYDROCHLORIDE

Take with food or a snack to minimize nausea and dizziness. Avoid grapefruit and grapefruit juice as they may increase trazodone levels and risk of QT prolongation. Avoid alcohol and tyramine-rich foods (e.g., aged cheeses, cured meats) to prevent hypertensive crisis.

Lactation Summary
INVEGA TRINZA

Paliperidone is excreted in human breast milk; M/P ratio not established. The relative infant dose is estimated at 2.8-5.1% of maternal weight-adjusted dose. Monitor infant for sedation, irritability, poor feeding, and extrapyramidal signs. Consider benefits of breastfeeding and need for maternal therapy.

TRAZODONE HYDROCHLORIDE

Enters breast milk in low levels. M/P ratio estimated at 0.1-0.2. Limited data suggest no adverse effects in infants but caution is advised. Monitor infant for drowsiness, poor feeding, and weight gain.

Pregnancy Dosing
INVEGA TRINZA

No established dosing adjustment guidelines for INVEGA TRINZA during pregnancy. Pregnancy may alter pharmacokinetics (e.g., increased clearance, volume of distribution), potentially requiring dose adjustments. Monitor clinical response and tolerability; consider more frequent dosing intervals or dose titration. Use lowest effective dose. Postpartum, return to pre-pregnancy dose as pharmacokinetics normalize.

TRAZODONE HYDROCHLORIDE

No specific dose adjustments established for pregnancy. Increased clearance and volume of distribution during pregnancy may reduce serum levels; consider therapeutic drug monitoring if clinically indicated. Start at lowest effective dose (e.g., 50-150 mg/day) and titrate gradually. Avoid abrupt discontinuation to prevent withdrawal symptoms.

Maternal Safety Status
INVEGA TRINZA
Category C
TRAZODONE HYDROCHLORIDE
Category A/B
Patient Counseling
INVEGA TRINZA

This medication is given as an injection once every 3 months by a healthcare professional.,Do not attempt to self-administer; it must be given by a doctor or nurse.,You must first receive two doses of the monthly injection (Invega Sustenna) before starting this medication.,Common side effects include injection site pain, sleepiness, dizziness, weight gain, and increased prolactin levels.,Avoid alcohol and grapefruit juice as they may increase side effects.,Seek emergency medical attention if you experience severe muscle stiffness, fever, confusion, or irregular heartbeat.,Inform your doctor if you are pregnant, breastfeeding, or planning to become pregnant.,Do not drive or operate heavy machinery until you know how this medication affects you.

TRAZODONE HYDROCHLORIDE

Take trazodone exactly as prescribed; do not double doses if a dose is missed.,Avoid alcohol and other CNS depressants (e.g., benzodiazepines, opioids) as they increase sedation and risk of falls.,Do not drive or operate heavy machinery until you know how trazodone affects you, especially during initial treatment or dose changes.,Seek immediate medical attention if you experience a painful or prolonged erection lasting more than 4 hours.,Report symptoms of serotonin syndrome: agitation, hallucinations, rapid heart rate, fever, muscle stiffness, nausea, vomiting, diarrhea.,Trazodone may cause dizziness or lightheadedness, especially when standing up; rise slowly from sitting or lying positions.,If you have a history of heart disease, your doctor may monitor your ECG (electrocardiogram) due to risk of QT prolongation.,Do not stop taking trazodone abruptly; taper under medical supervision to avoid withdrawal symptoms.,Store at room temperature, away from heat, moisture, and light.,This medication can be taken with or without food, but taking it with food may reduce the risk of an upset stomach.