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lithium vs spironolactone

Side-by-side comparison of lithium and spironolactone. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

moderate Known Drug Interaction

Lithium: Increased risk of lithium toxicity ( 7.2 ). Examples of drugs that can increase potassium include: ACE inhibitors angiotensin receptor blockers non-steroidal anti-inflammatory drugs (NSAIDs) heparin and low molecular weight heparin trimethoprim 7.2 Lithium Like other diuretics, spironolactone reduces the renal clearance of lithium, thus increasing the risk of lithium toxicity. Monitor lithium levels periodically when spironolactone is co-administered [see Clinical Pharmacology (12.3) ] .

Recommendation: Your doctor should check your lithium blood levels regularly while you are taking both medications.

Drug Class
lithium Mood Stabilizer
spironolactone Potassium-Sparing Diuretic / Aldosterone Antagonist
Type
lithium Prescription
spironolactone Prescription
Summary
lithium

Lithium is a mood stabilizer medicine. It helps to balance mood swings.

spironolactone

Spironolactone is a medicine that helps remove extra fluid from your body and lower blood pressure. It also helps your heart work better if you have heart failure.

What It Treats
lithium

Lithium is used to treat bipolar disorder. Bipolar disorder causes unusual shifts in mood, energy, activity levels, and concentration. Lithium helps to control the extreme highs (mania) and lows (depression) of this condition.

spironolactone

Spironolactone is used to treat heart failure by reducing fluid build-up and helping you live longer. It also treats high blood pressure, which can lower your chance of having a stroke or heart attack. This medicine can also manage fluid build-up caused by liver problems or a kidney problem called nephrotic syndrome. It can also treat a condition where your body makes too much of a hormone called aldosterone.

How It Works
lithium

Lithium affects the flow of sodium in nerve and muscle cells in the body. This helps to stabilize your mood. It may also affect other chemical messenger systems in the brain.

spironolactone

Spironolactone belongs to a class of drugs called aldosterone antagonists. It works by blocking the effects of aldosterone, a hormone that causes your body to hold onto salt and water. By blocking aldosterone, spironolactone helps your body get rid of extra fluid and salt, which lowers blood pressure and reduces strain on the heart.

Common Side Effects
lithium
  • Tremor (shaking)
  • Nausea
  • Increased weight
  • Fatigue (feeling tired)
  • Vomiting
spironolactone
  • Breast enlargement in men
  • Dizziness
  • Headache
FAERS Reports
lithium
  • Poisoning from different substances 2,179
  • The drug is reacting with another medicine 1,526
  • Shaking 1,463
  • Feeling sick to your stomach 1,344
  • Gaining weight 1,153
spironolactone
  • Difficulty breathing 10,389
  • Tiredness 8,179
  • Feeling sick to your stomach 7,818
  • Loose stools 7,416
  • Sudden kidney damage 6,785
Serious Warnings
lithium

Lithium levels in your blood need to be monitored closely by your doctor. Too much lithium can be toxic and cause serious side effects. Make sure to attend all scheduled blood tests.

spironolactone

Spironolactone can cause your potassium levels to get too high, which can be dangerous. Your doctor will check your potassium levels regularly, especially if you have kidney problems or are taking other medicines that can raise potassium. This medicine can also cause low blood pressure or make kidney problems worse. Tell your doctor if you have side effects.

Pregnancy
lithium

Lithium can harm your unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. Lithium can pass into breast milk and may harm a nursing infant. Talk to your doctor about the best way to feed your baby if you are taking lithium.

spironolactone

Spironolactone may affect the sex organs of a baby boy if taken during pregnancy. Talk to your doctor if you are pregnant or plan to become pregnant. It is not known if spironolactone passes into breast milk, so talk to your doctor about the best way to feed your baby if you are taking this medicine.

How to Read This lithium vs spironolactone Comparison

lithium is classified in the Mood Stabilizer drug class, while spironolactone sits within the Potassium-Sparing Diuretic / Aldosterone Antagonist class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, lithium has 7,665 submissions while spironolactone has 40,587. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known moderate interaction flagged in FDA labeling, attributed to spironolactone makes it harder for the kidneys to remove lithium from the body. this can cause lithium to build up to dangerous levels.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot substitute for clinical judgment. Effectiveness, tolerability, drug-drug interactions with your other medications, kidney and liver function, pregnancy status, insurance formulary, and price all feed into a decision that only a licensed prescriber can make responsibly. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This page is for educational purposes only, is not medical advice, and should not be used to self-switch between lithium and spironolactone - always consult your physician or pharmacist first.

Important: This comparison is for informational purposes only. Drug effects vary between individuals. Always consult your doctor or pharmacist for personalized medical advice.