Lithium for Bipolar Disorder

Lithium is a salt-based medicine that has been used for bipolar disorder for decades, and it is still the reference point for long-term treatment. The FDA label covers manic and mixed episodes of bipolar I and maintenance treatment, and NICE describes lithium as the most effective long-term treatment for bipolar disorder. It also comes with real responsibilities: regular blood tests, attention to kidney and thyroid health, and care with heat and certain common medicines. This page covers why lithium is used, what it can do to the body, and the interactions to know. Blood-level timing and toxicity signs have their own page.

What lithium is approved and recommended for

The current lithium carbonate label approves it as a single treatment for acute manic and mixed episodes of bipolar I disorder and for maintenance treatment. Some lithium products are FDA-approved for bipolar I in children 7 and older.

Guidelines give it a central place:

• NICE CG185 says to offer lithium as a first-line, long-term treatment and to explain that it is the most effective long-term treatment for bipolar disorder.
• CANMAT/ISBD 2018 lists lithium as a first-line maintenance option for both bipolar I and bipolar II, and as a first-line option for acute mania and bipolar I depression.
• The VA/DoD 2023 guideline recommends lithium or quetiapine to prevent manic episodes from returning (a strong recommendation) and suggests them for preventing depressive episodes.

How lithium compares with the other options is laid out in bipolar disorder medications explained.

Lithium and suicide risk

People with bipolar disorder face a much higher risk of suicide than the general population, so this question matters. NIMH states that lithium can decrease the risk of suicide.

The best-known evidence is a 2013 BMJ meta-analysis of 48 randomized trials with 6,674 participants, which found fewer suicides and fewer deaths from any cause in people taking lithium compared with placebo. It did not find a clear effect on self-harm. Large observational studies point the same way.

Not every analysis agrees. The VA/DoD guideline notes that a 2021 network meta-analysis of shorter trials did not confirm the effect. So the fair summary is that strong evidence suggests lithium is associated with lower suicide risk, not that it is proven to prevent suicide. It is one protective factor among several, alongside therapy, a crisis plan and people who know your warning signs.

Before starting lithium

The label lists checks to do before the first dose: kidney function, vital signs, electrolytes, thyroid function, a review of other medicines, and pregnancy status. NICE adds weight or BMI, calcium and a full blood count.

The lithium Medication Guide asks people to tell their provider about:

• Kidney, heart, breathing or thyroid problems.
• Pregnancy, plans to become pregnant, or breastfeeding. The Medication Guide says not to breastfeed during lithium treatment.
• Every other medicine and supplement, including antidepressants, antipsychotics, migraine medicines called triptans, tramadol, fentanyl and St. John's wort.

None of this rules lithium out automatically. It shapes the starting plan, the monitoring schedule and which other medicines need to change. It is also a good moment to agree on how you will reach your prescriber if side effects show up between visits.

Common side effects

According to the label, the most common side effects in adults are fine hand tremor, passing more urine, mild thirst, nausea and a general feeling of discomfort when treatment starts. In children and teens, nausea or vomiting, passing more urine, thyroid changes, tremor, thirst and dizziness are among the most common.

Many early effects settle. Others, such as tremor or thirst, may persist and are worth raising, because timing, formulation or dose changes can sometimes help. A coarse tremor (larger and jerkier than a fine tremor), new unsteadiness, vomiting or diarrhea is different: it can be an early sign of a level that is too high and needs a same-day call.

Kidneys, thyroid and calcium

Lithium is cleared by the kidneys, which is why kidney health and lithium are closely linked. The label lists several long-term effects to monitor:

• Kidneys: lithium can reduce the kidneys' ability to concentrate urine (sometimes as nephrogenic diabetes insipidus, with heavy urination and thirst), and long-term use is associated with chronic kidney disease. Kidney function is checked during treatment.
• Thyroid: lithium can cause an underactive thyroid and, less often, an overactive one. An underactive thyroid can look like depression, so thyroid tests are part of routine care. It is usually treatable without stopping lithium.
• Calcium: long-term use is associated with overactive parathyroid glands and high calcium levels, so calcium is checked too.

NICE recommends checking weight, kidney function, calcium and thyroid every six months for people on lithium, and more often if results start to change. Our lab monitoring guide covers these tests in general; how the blood lithium level itself works is in lithium levels explained.

Interactions: medicines that raise or lower lithium

Because lithium has a narrow safety margin, other medicines that change how the kidneys handle it matter a lot. The label lists these as raising lithium levels:

• NSAIDs, including over-the-counter ibuprofen and naproxen. NICE advises people on lithium not to take over-the-counter NSAIDs.
• ACE inhibitors and ARBs, common blood pressure medicines (for example, names ending in "-pril" or "-sartan").
• Diuretics (water pills), including thiazides.
• Metronidazole and related antibiotics.

Others lower lithium levels, including acetazolamide, theophylline and alkalinizing agents. Lithium combined with serotonergic medicines can rarely cause serotonin syndrome, and with antipsychotics the label warns of a rare encephalopathic syndrome, so new confusion or fever needs urgent attention.

Before any new prescription, including from urgent care or a dentist, tell the prescriber you take lithium. Ask a pharmacist before buying cold or pain medicines. Alcohol is covered in alcohol and psychiatric medication.

Heat, sweating and illness

Losing water and salt concentrates lithium in the blood. The label lists fever, dehydration and changes in sodium among the factors that increase toxicity risk, and advises a normal diet with salt and good hydration. NICE tells people to keep fluid intake up, especially after sweating from exercise, hot weather or fever.

That matters in a Texas or Arizona summer. Long days outdoors, heavy exercise, a stomach bug or a fever can each raise a lithium level within days. A crash diet or sudden low-salt diet can also shift it. Psychiatric medication in extreme heat has practical tips for hot months. If you cannot keep fluids down, contact your prescriber that day.

Pregnancy, teens and stopping

Lithium in pregnancy carries a small increased risk of certain heart defects, smaller than once believed, and levels need close follow-up around delivery. Do not stop it on your own if you become pregnant; see bipolar disorder and pregnancy. For young people, bipolar medication for teens explains the pediatric approvals.

If lithium is ever stopped, NICE advises reducing it gradually over at least four weeks, preferably up to three months, with close watch for relapse during the taper and for three months after. Stopping abruptly raises the risk of an episode returning.

At Willow & Stone

Dr. Stacey Forbes, PMHNP-BC, sees people with bipolar disorder in Arlington, Texas, and by telehealth in Texas, New Mexico, Florida, Alaska, Arizona, Colorado and Washington. If you already take lithium or are wondering whether it fits, medication options are discussed at your evaluation, and labs are ordered as needed. See bipolar disorder treatment at Willow & Stone or return to the bipolar disorder guide.

Common Questions

Sources & Further Reading

• DailyMed: Lithium carbonate prescribing information and Medication Guide (2026)
• NICE CG185: Bipolar disorder: assessment and management (last updated 2 September 2025)
• Yatham LN et al. CANMAT and ISBD 2018 guidelines for the management of patients with bipolar disorder. Bipolar Disord 2018 (PMID 29536616)
• VA/DoD Clinical Practice Guideline for the Management of Bipolar Disorder (Version 2.0, 2023)
• Cipriani A et al. Lithium in the prevention of suicide in mood disorders: updated systematic review and meta-analysis. BMJ 2013 (PMID 23814104)
• NIMH: Bipolar Disorder (NIH Pub. No. 25-MH-8088, revised 2025)

This article is general education, not a diagnosis or advice for your situation. Do not start, stop, or change a medication without talking to the clinician who prescribes it; stopping a mood stabilizer suddenly can trigger relapse.