Lurasidone (Latuda) is an atypical, second-generation antipsychotic medication used to manage certain mood and mental health conditions. It works by modulating specific neurotransmitters, particularly serotonin and dopamine, in the brain. Understanding precise dosage requirements is important for patient safety and maximizing therapeutic benefit. This article details the standard dosing, administration requirements, and necessary modifications for Lurasidone. This information is for educational purposes only and is not a substitute for professional medical advice.
Conditions Treated by Lurasidone
The FDA has approved Lurasidone for two major psychiatric illnesses, with specific dosing regimens tailored to each indication.
The first use is the management of schizophrenia in adults and adolescents aged 13 to 17 years. This chronic condition requires ongoing treatment.
The second indication is the treatment of major depressive episodes associated with Bipolar I Disorder (bipolar depression). For this condition, Lurasidone is approved for use in adults as monotherapy or as an adjunctive therapy alongside established mood stabilizers like lithium or valproate.
Standard Starting and Maintenance Doses
Lurasidone dosing is condition-specific, but it is always taken once daily. For adult patients with schizophrenia, the initial recommended starting dose is 40 mg per day. This dose generally does not require a titration period. The effective dosage range for schizophrenia is 40 mg to 160 mg per day, with 160 mg being the maximum recommended daily dose.
The dosing protocol for depressive episodes associated with Bipolar I Disorder begins lower. For adults receiving Lurasidone (as monotherapy or adjunctively), the recommended starting dose is 20 mg once daily. The effective dosage range for bipolar depression is 20 mg to a maximum recommended daily dose of 120 mg. Clinical trials suggest that doses above 60 mg per day in monotherapy may not provide additional efficacy for all patients.
Maintenance dosing involves finding the lowest effective dose that successfully manages symptoms long-term. For both indications, a healthcare provider evaluates the patient’s response and tolerability before increasing the dose. Doses are typically adjusted in small increments (20 mg or 40 mg) to balance symptom control and side effect management.
Essential Food Requirements for Absorption
A non-negotiable requirement for Lurasidone administration is that it must be taken with food for proper absorption. Specifically, the medication must be consumed with a meal containing at least 350 calories. This requirement stems from the drug’s pharmacokinetic properties; Lurasidone is poorly soluble in water, making its absorption highly dependent on the presence of food.
Consuming the dose with adequate calories significantly impacts the drug’s bioavailability. Studies show that taking Lurasidone with a meal increases total drug exposure (AUC) by approximately two-fold compared to taking it on an empty stomach. The peak concentration (Cmax) can increase by about three-fold. Failure to meet this caloric threshold results in subtherapeutic plasma concentrations, which can significantly reduce the medication’s effectiveness.
Required Dose Modifications
The standard doses of Lurasidone must be adjusted for certain patients to prevent drug accumulation and potential toxicity. One major consideration is the presence of impaired organ function, particularly in the kidneys and liver, as these organs are responsible for metabolizing and clearing the medication from the body.
Organ Impairment
Patients diagnosed with moderate to severe renal impairment, defined by a creatinine clearance below 50 milliliters per minute, should start at 20 mg per day, with the maximum daily dose capped at 80 mg. Similar dose limitations apply to patients with moderate hepatic impairment, where the maximum daily dose should not exceed 80 mg. For individuals with severe hepatic impairment, the restriction is even stricter, limiting the maximum recommended daily dose to 40 mg. These adjustments are necessary because the compromised function of these organs prolongs the half-life of Lurasidone, keeping it in the body longer and increasing the risk of adverse effects.
Drug-Drug Interactions
Another category requiring dose modification involves drug-drug interactions, as Lurasidone is primarily metabolized by the liver enzyme CYP3A4. Co-administration with strong CYP3A4 inhibitors, such as certain antifungal agents like ketoconazole or antiviral drugs, is contraindicated because they dramatically increase Lurasidone levels, which can lead to toxicity. Conversely, strong CYP3A4 inducers, like the antibiotic rifampin, are also contraindicated because they accelerate Lurasidone metabolism, rapidly lowering its concentration to ineffective levels.
When Lurasidone is co-administered with moderate CYP3A4 inhibitors, such as diltiazem, the Lurasidone dose must be reduced to half of the original maintenance dose. If a patient is starting Lurasidone while already taking a moderate inhibitor, the starting dose should be 20 mg per day, and the maximum dose should not exceed 80 mg per day. Conversely, if a patient is taking a moderate CYP3A4 inducer, the Lurasidone dose may need to be carefully increased after about seven days to counteract the accelerated breakdown of the drug.