A patient in his 20s recently came to see me in a state of severe distress. He described feeling consumed by his thoughts, constantly anxious, unable to function, and deeply exhausted. His sleep had collapsed. His sense of identity felt lost. He was experiencing persistent passive suicidal thoughts, not because he wanted to die, but because everything felt overwhelming and unrelenting.

Within three days of starting low-dose lithium at 150 milligrams (mg), those thoughts were gone. Not improved. Gone. His energy began to return. He described waking up and feeling, for the first time in a long time, that he could actually face his day. This is not an isolated case.

Lithium is one of the most misunderstood medications in psychiatry. It is often reserved for bipolar disorder, avoided due to concerns about side effects, and overshadowed by newer medications perceived as safer or easier to use. But in that shift, something important has been lost.

The proven anti-suicidal effects of lithium

Lithium has over 40 years of evidence supporting its use, particularly in reducing suicidal ideation and suicide risk. It is one of the very few medications in psychiatry that can consistently make that claim. There are others. Clozapine has demonstrated anti-suicidal effects but carries significant side effect burden and monitoring requirements. Ketamine can produce rapid reductions in suicidal ideation, but we do not yet have robust long-term outcome data related to suicidality.

Lithium stands apart in both its consistency and its long-term data. Part of the issue is lithium’s narrow therapeutic window at higher doses. In traditional bipolar treatment, doses often range from 900 mg to 1,800 mg daily, targeting specific serum levels. At those levels, the difference between therapeutic benefit and toxicity can be relatively small, requiring careful monitoring and contributing to its reputation.

But this is not the whole story. Lithium is not just a drug. It is a naturally occurring element, one of the first on the periodic table, and it is present in trace amounts in our environment, including drinking water. Studies over several decades have shown that regions with higher naturally occurring lithium levels in drinking water, often in the range of approximately 0.1 to 0.3 mg per day of intake, have lower rates of suicide and, in some cases, lower rates of violent crime. Notably, populations in areas closer to the higher end of that range, around 0.3 mg per day, have demonstrated the most consistent protective associations.

That should give us pause. It suggests that lithium may not simply be a treatment for pathology, but a micronutrient that plays a role in brain stability.

How lithium stabilizes the underlying biology of the brain

At the level of the brain, lithium affects multiple systems. It modulates glutamate, one of the primary excitatory neurotransmitters involved in anxiety, mood instability, and intrusive thought loops. It enhances neurotrophic factors such as brain-derived neurotrophic factor (BDNF), supporting neuronal growth and resilience. It inhibits glycogen synthase kinase-3 (GSK-3), a key enzyme involved in inflammation, circadian regulation, and cellular signaling. It reduces oxidative stress and appears to protect neurons from degeneration.

This is why lithium is considered disease modifying. It does not simply suppress symptoms. It appears to stabilize the underlying biology of the brain in a way that few psychiatric medications do. And yet, our clinical approach to lithium has remained narrow. We have been trained to think in terms of serum levels rather than patient response. We titrate to numbers instead of listening to what is happening clinically.

The clinical potential of low-dose lithium

In my practice, I have used low-dose lithium with dozens of patients over the years and have consistently observed meaningful improvements, including cases of rapid resolution of suicidal ideation. While individual responses can vary, the consistency of benefit has been notable. One patient of mine had experienced suicidal ideation for over 20 years and had a prior attempt. Within five days of starting lithium, those thoughts resolved. Nearly three years later, they have not returned. He remains stable on 300 mg of lithium carbonate daily.

This is not a fringe observation. It is something many clinicians who are prescribing low-dose lithium are seeing but not widely discussing. Perhaps the problem is not lithium. Perhaps the problem is how we have been taught to think about it. We have become comfortable prescribing medications that are newer, more heavily marketed, and perceived as safer, while overlooking one of the most well-studied and potentially impactful treatments we have.

We treat to lab values instead of treating the patient. We aim for standard dosing instead of asking what is the lowest effective dose. And in doing so, we may be missing an opportunity. Lithium does require thoughtful use and appropriate monitoring. It is not appropriate for every patient. But the reflexive avoidance of lithium, particularly at low doses, deserves reconsideration.

If a treatment can reduce suicidal ideation within days, stabilize mood, and support the biology of the brain itself, it should not be sitting on the sidelines. Sometimes the most powerful treatments are not the newest ones. Lithium may not be underused because it is ineffective, but because we have overlooked its potential in patients for whom our standard approaches, often medications that take weeks to work, are not enough.

Carrie Friedman is a dual board-certified psychiatric and family nurse practitioner and the founder of Brain Garden Psychiatry in California. She integrates evidence-based psychopharmacology with functional and integrative psychiatry, emphasizing root-cause approaches that connect neuro-nutrition and gut–brain science, metabolic psychiatry, immunology, endocrinology, and mind–body lifestyle medicine. Carrie’s clinical focus bridges conventional psychiatry with holistic strategies to support mental health through nutrition, physiology, and sustainable lifestyle interventions. Her professional writing explores topics such as functional medicine, autism, provider well-being, and medical ethics.