Lithium Drug Interactions

by on May 12, 2012

Lithium is a prescription drug that interacts with a number of different medications. Most serious lithium drug interactions occur with selective serotonin reuptake inhibitors, or SSRIs. Taking lithium with these medications increases their pharmacological effects, which can lead to serotonin syndrome, a potentially fatal condition that causes overstimulation of the brainstem.

Major Lithium Drug Interactions

  • SSRIs – These medications include Celexa, Cymbalta, Effexor, Lexapro, Prozac and Zoloft. Taking lithium with these medications increases serotonergic activity. The exact mechanism for why this happens is not known. People taking lithium with SSRIs need to have their lithium levels closely monitored and adjusted to prevent ill effects.
  • Aldactone – This medication reduces renal clearance of lithium from the body, which can cause toxic levels of lithium to build up in the blood. It is highly recommended that these two medications not be prescribed together.
  • Bupropion – Combining bupropion with lithium increases risk of seizures. Bupropion dosage needs to be kept low when taking lithium. If a seizure occurs, bupropion should be discontinued immediately.
  • Darvocet – Lithium taken with sedatives, tranquilizers or muscle relaxants can increase the effects on the central nervous system. The elderly and people with emotional issues need to be monitored closely when taking Darvocet and lithium together.
  • Fleet Enema – Bowel cleansing phosphate and sulfate preparations lower the seizure threshold, and taken with lithium, increases seizure risk.
  • Haldol – When this cardiac medication is taken with lithium it can cause arrhythmia, or a prolongation of the QT wave. Although these medications have been administered together without ill effects, there have been a few cases of encephalopathic syndrome, which leads to permanent brain damage.
  • Immune Globulin Intravenous and Subcutaneous Preparations – As a nephrotoxic medication, lithium combined with immune globulin can lead to kidney impairment. Adequate hydration and close monitoring are recommended when these medications are given together.
  • Lasix (Furosemide) – Loop diuretics, like Lasix, may cause toxic levels of lithium in the blood and should not be prescribed together.
  • Iohexal – Although the evidence is limited, lithium taken with iohexal may lead to seizures.

Moderate Interactions

  • Advil – The exact mechanism is not understood, but lithium combined with ibuprofen medications like Advil can cause toxic levels of lithium in the blood. Lithium drug interactions with Advil are rare, but close monitoring is recommended when taking these two medications together.
  • Benadryl – The elderly need to be especially cautious when taking the allergy medicine Benadryl with lithium. Together these medications have a depressant effect on both the respiratory and central nervous systems.
  • Captopril – Coadminstration of ACE inhibitors like captopril with lithium can lead to toxic levels of lithium in the blood. It can also have toxic effects on the kidneys.

In addition to drugs, lithium also moderately interacts with caffeine and alcohol. Caffeine withdrawal from the diet increases blood levels of lithium. As a central nervous system depressant, alcohol taken with lithium can have a pronounced effect on psychomotor skills and judgment.