Schizophrenia is a chronic mental health condition that can significantly affect a person’s thoughts, feelings, and behaviors. Individuals experiencing schizophrenia may have difficulty distinguishing what is real from what is not, leading to a range of symptoms that impact daily functioning. While antipsychotic medications are the primary treatment for managing the core psychotic symptoms of schizophrenia, other medications are sometimes used to address specific aspects of the illness.
Lithium is a medication primarily used for bipolar disorder, a condition with significant mood swings. While not a standalone treatment for core schizophrenia symptoms, lithium can play an adjunctive role in managing certain features. Its use in schizophrenia focuses on specific co-occurring symptoms rather than directly targeting primary psychotic experiences.
Lithium’s Specific Application in Schizophrenia
Lithium is not a primary or standalone medication for core psychotic symptoms like hallucinations or delusions. Antipsychotics remain the foundational treatment. However, many individuals with schizophrenia may not fully respond to antipsychotics alone, or they may experience additional symptoms that benefit from further intervention.
Lithium is employed as an add-on therapy in specific clinical scenarios. It is particularly useful for managing co-occurring mood symptoms, such as depression, mania, or mood instability. This is particularly relevant in schizoaffective disorder, which combines features of schizophrenia and a mood disorder.
Beyond mood stabilization, lithium can also help reduce aggression or impulsivity. While evidence is varied, some guidelines identify its use for excitement, agitation, and aggressive behavior. If there’s a family history of bipolar disorder alongside schizophrenia, lithium might be considered due to its established efficacy in mood regulation. Its main contribution is to stabilize mood and behavior, not directly alleviate psychotic symptoms.
Expected Effects and Potential Side Effects
As an adjunctive therapy in schizophrenia, its effects primarily involve mood stabilization and reduced agitation or aggression. A more regulated emotional state can indirectly improve overall functioning and response to primary antipsychotics. While its direct impact on psychotic symptoms is not well-established, some evidence suggests benefits when combined with antipsychotics.
Despite its benefits, lithium therapy is associated with potential side effects. Common side effects include increased thirst and frequent urination, potentially leading to dehydration. Other common issues include mild hand tremors, nausea, vomiting, or diarrhea, especially when treatment begins. Some may also report a metallic taste, dry mouth, or cognitive dulling.
More serious side effects require careful monitoring. Long-term lithium use can affect kidney function, potentially leading to swollen hands or ankles, fatigue, and changes in urine output. Thyroid problems, particularly an underactive thyroid (hypothyroidism), can also develop, presenting as tiredness, weight gain, depression, dry skin, or cold intolerance.
Lithium toxicity, which occurs when blood levels are too high, is a medical emergency. Symptoms include severe tremor, confusion, slurred speech, unsteadiness, severe nausea, vomiting, and an irregular pulse. If these symptoms appear, immediate medical attention is necessary, and lithium should be stopped.
Administering and Monitoring Lithium Therapy
Lithium treatment requires careful medical supervision due to its narrow therapeutic index, meaning a small difference exists between an effective and toxic dose. Before starting lithium, a thorough baseline assessment is conducted, including weight, blood tests for kidney function (urea and electrolytes, estimated glomerular filtration rate), thyroid function, and calcium levels. An electrocardiogram (ECG) may also be recommended, especially for those with existing cardiovascular conditions or risk factors.
Initial lithium dosing is typically low and gradually increased based on patient response and blood levels. Regular blood tests ensure lithium levels remain within the therapeutic range (typically 0.6-1.2 mEq/L) and monitor kidney and thyroid function. Blood samples for lithium levels are ideally taken 12 hours after the last dose to measure the “trough” level, reflecting the lowest concentration before the next dose.
During initial treatment or after a dose change, lithium levels are checked frequently, often weekly, until stable. Once stable, monitoring typically occurs every three to six months for lithium levels, and every six months for kidney and thyroid function. Several factors can influence lithium levels, including dehydration (from fever, vomiting, or diarrhea), significant changes in dietary sodium intake, and interactions with other medications like non-steroidal anti-inflammatory drugs (NSAIDs) or diuretics. Consistent adherence to the prescribed regimen is important for maintaining stable levels and minimizing risks. Patients are educated on toxicity signs and instructed to seek immediate medical attention if symptoms arise.