Lithium Carbonate

How Does Lithium Carbonate Work?

The exact mechanism of action of Lithium Carbonate as a mood stabilizer is not fully understood—the FDA-approved labeling explicitly states this. Lithium is an element (atomic number 3) that, when ingested as lithium carbonate, dissociates into lithium ions (Li⁺) that enter the brain. There it interacts with multiple biological systems simultaneously.

Current scientific understanding points to several mechanisms working together: lithium alters sodium transport in nerve cell membranes and shifts the metabolism of catecholamines (norepinephrine, dopamine); it enhances serotonin synthesis and release; and it inhibits GSK3-beta, an enzyme linked to mood regulation, neuroplasticity, and cell survival. Inhibiting GSK3-beta activates neuroprotective signaling pathways (the Akt/mTOR pathway), which may explain why long-term lithium users show greater brain gray matter volume than untreated patients with bipolar disorder.

What is clear is lithium's clinical effectiveness: it is one of the most evidence-based treatments in all of psychiatry, with more than 70 years of clinical evidence supporting its use for bipolar disorder. It also has a unique, well-documented anti-suicidal effect—reducing suicide rates approximately 9-fold—that is not replicated by any other mood stabilizer.

How Hard Is It to Find Lithium Carbonate in Stock?

As of 2026, Lithium Carbonate is not on the FDA's Drug Shortages Database, and national supply from multiple generic manufacturers is stable. The standard 300 mg tablets and capsules are widely available at most pharmacies. Lithium Carbonate receives a findability score of 82/100—generally available with occasional localized stocking gaps for specific strengths.

Some patients still experience difficulty filling their prescription, particularly for less common formulations: the 150 mg capsule, 450 mg ER tablet, and oral solution are stocked at fewer pharmacies than the standard 300 mg tablet. Pharmacy-level variability—different wholesale supplier contracts, local demand patterns, temporary backorders—can cause localized gaps even when the medication is broadly available.

If you are having trouble finding Lithium Carbonate in stock at your local pharmacy, medfinder can help. You provide your medication name, dose, and location, and medfinder calls pharmacies near you to check which ones have it in stock—then texts you the results. This is particularly useful for patients on less common strengths who have already been turned away by one or two pharmacies.

Who Can Prescribe Lithium Carbonate?

Lithium Carbonate is not a controlled substance, so any licensed prescriber with full prescribing authority can order it. However, because lithium requires careful monitoring of serum levels, renal function, and thyroid function, and has a narrow therapeutic index, most patients benefit from working with a prescriber experienced in managing bipolar disorder. The following provider types regularly prescribe and manage lithium therapy:

Psychiatrists — most commonly initiate lithium therapy; best equipped to diagnose bipolar disorder and manage complex presentations

Psychiatric-Mental Health Nurse Practitioners (PMHNPs) — full prescribing authority in most states; specialize in psychiatric medication management

Primary Care Physicians — often co-manage stable long-term patients; may initiate based on psychiatry consultation

Internists — manage lithium in adult patients, often in areas with limited psychiatric access

Pediatricians / Child and Adolescent Psychiatrists — prescribe for patients aged 7 and older, with weight-based dosing

Physician Assistants (PAs) — with psychiatric supervision, PAs may prescribe and manage lithium

Lithium Carbonate can be prescribed via telehealth in all 50 states. Because it is not a controlled substance, there are no federal restrictions on telehealth prescribing. Telehealth psychiatry services including Talkiatry, Talkspace, Klarity, and others regularly prescribe lithium. Patients will still need to complete blood work (lithium levels, renal function, thyroid) at a local lab facility.

Is Lithium Carbonate a Controlled Substance?

No. Lithium Carbonate is not a controlled substance and has no DEA scheduling. It can be prescribed by any licensed provider—including primary care physicians, psychiatrists, nurse practitioners, and physician assistants—without the special DEA registration requirements that apply to controlled substances like stimulants or benzodiazepines.

Because it is not controlled, Lithium Carbonate can be prescribed electronically or called into a pharmacy, refilled without restrictions, and prescribed via telehealth in all 50 states without the in-person visit requirements of the Ryan Haight Act (which applies only to controlled substances). There are no monthly fill limits based on DEA scheduling.

While not controlled, Lithium Carbonate does require careful medical oversight due to its narrow therapeutic index and the requirement for regular serum level monitoring. Prescribers typically require current lab results (lithium levels, renal function, thyroid function) before authorizing refills, which is a clinical—not regulatory—requirement.

Common Side Effects of Lithium Carbonate

These side effects are common, especially when starting therapy or after dose increases, and often improve with time:

Fine hand tremor

Increased thirst and urination (polyuria/polydipsia)

Nausea and diarrhea (reduced by taking with food)

Weight gain (modest, typically 5–10 lbs)

Cognitive dulling or mild memory difficulties

Hair thinning (may be related to thyroid changes)

Acne or psoriasis exacerbation

Serious Side Effects of Lithium Carbonate

Lithium toxicity (worsening tremor, confusion, ataxia, seizures, coma, death — seek emergency care immediately)

Renal impairment (long-term use; monitored with regular creatinine and eGFR testing)

Hypothyroidism (develops in up to 40% of long-term users; monitored with TSH testing)

Hypercalcemia/hyperparathyroidism (monitored with annual serum calcium)

Serotonin syndrome (when combined with SSRIs, SNRIs, or MAOIs)

Cardiac arrhythmias (ECG changes, prolonged QT; Brugada syndrome risk)

Teratogenicity (risk of Ebstein's anomaly and other cardiac malformations in pregnancy; lowest effective dose recommended)

Final Thoughts on Lithium Carbonate

Lithium Carbonate remains one of psychiatry's most important medications after more than 70 years of clinical use. It is the first-line treatment for Bipolar I Disorder maintenance in most clinical guidelines, the only mood stabilizer on the WHO's Essential Medicines List, and the only psychiatric medication with documented anti-suicidal effects. For patients who respond to it, lithium can be life-changing—and in some cases, life-saving.

Its challenges are real: it requires regular blood monitoring, has a narrow therapeutic index that makes drug interactions and dehydration clinically significant, and has long-term effects on kidney and thyroid function that require ongoing attention. But for patients on appropriate doses with regular monitoring, lithium is safe and highly effective for long-term bipolar management.

If you are on Lithium Carbonate and have trouble finding your specific strength or formulation at a local pharmacy, medfinder can help. Provide your medication name, dose, and location, and medfinder calls pharmacies in your area to find which ones have it in stock—then texts you the results.