What the label lists and what reports show
Lithium side effects
Lithium's FDA label lists its adverse reactions in its own words. FAERS holds 41,678 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is toxicity to various agents (3,424 reports).
- Generic listed
- Boxed warning
Check it at the source: the lithium FDA label on DailyMed (effective December 23, 2025, Glenmark Pharmaceuticals Inc., USA); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of lithium carbonate capsules?See “What is the most important information I should know about lithium carbonate capsules? Lithium carbonate capsules may cause serious side effects, including: • kidney problems. People who take lithium carbonate capsules may have to urinate often (polyuria) and have other kidney problems that may affect how their kidneys work. These problems can happen within a few weeks of starting to take lithium carbonate capsules or after taking lithium carbonate capsules for a long time. • low levels of sodium (salt) in your blood (hyponatremia). Lithium carbonate capsules can cause you to lose sodium. Talk to your healthcare provider about your diet and how much fluid you are drinking when starting lithium carbonate capsules. If you have been sweating more than usual or have had diarrhea, you may need extra salt and more fluids. Talk to your healthcare provider if this happens. […]
Source: FDA drug label, Glenmark Pharmaceuticals Inc., USA, effective December 23, 2025 (SPL set 63b3790f-a9b5-47f4-bae1-ddf8b43c13c1), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsThe following adverse reactions are described in greater detail in other sections: • Acute Lithium Toxicity [see Warnings and Precautions ( 5.1 )] • Lithium-Induced Polyuria [see Warnings and Precautions ( 5.2 )] • Hyponatremia [see Warnings and Precautions ( 5.3 )] • Lithium-Induced Chronic Kidney Disease [see Warnings and Precautions ( 5.4 )] • Encephalopathic Syndrome [see Warnings and Precautions ( 5.5 )] • Serotonin Syndrome [see Warnings and Precautions ( 5.6 )] • Hypothyroidism or Hyperthyroidism [see Warnings and Precautions ( 5.7 )] • Hypercalcemia and Hyperparathyroidism [see Warnings and Precautions ( 5.8 )] • Unmasking of Brugada Syndrome [see Warnings and Precautions ( 5.9 )] • Pseudotumor Cerebri [see Warnings and Precautions ( 5.10 )] Common Adverse Reactions: • Adult Patients: fine hand tremor, polyuria, mild thirst, nausea, general discomfort during initial treatment …
A table the label prints in its adverse reactions section without a title; its column headings name the groups compared
| System Organ Class/ Preferred Term | Placebo N=28 % | Lithium N=53 % |
|---|---|---|
| Nausea/vomiting | 29 | 57 |
| Fatigue | 4 | 26 |
| Polyuria (Including Enuresis) | 14 | 38 |
| Increased TSH | 0 | 25 |
| Thirst/polydipsia | 11 | 28 |
| Decreased appetite | 4 | 9 |
| Ataxia/gait disturbance | 0 | 13 |
| Blurry vision | 0 | 9 |
| Disorientation | 0 | 6 |
| Dizziness | 7 | 23 |
| Tremor | 7 | 32 |
| Rash/dermatitis | 0 | 13 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
Source: FDA drug label, Glenmark Pharmaceuticals Inc., USA, effective December 23, 2025 (SPL set 63b3790f-a9b5-47f4-bae1-ddf8b43c13c1), via openFDA; the full label on DailyMed
What do FAERS reports show?
41,678 reports list lithium among the medicines taken, each a report of something that happened, not proof the medicine caused it; 3,280 are coded as a death and 16,962 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 19 reactions below, 8 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Lithium: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions