Mood Stabilizing Medications

Lithium

Lithium helps control acute mania and the acute manic episodes associated with bipolar disorder and is used prophylactically to prevent recurrence of mania or depression.

Prototype and Other Medications

The prototype mood stabilizer medication is lithium carbonate, also called Lithobid. This is the primary and preferred medication for treating the mania associated with bipolar disorder.

Expected Pharmacologic Action

How lithium regulates mood is not entirely clear. However, lithium does change the transport of sodium ions in nerve cells, and that action alters the metabolism of catecholamines, the fight-or-flight hormones the adrenal glands release in response to stress. These actions help to decrease the mania associated with bipolar disorder. This medication also offers protection against neuronal atrophy and actually promotes neuronal growth, contributing to its therapeutic effects.

Adverse Drug Reactions

Adverse medication reactions to lithium will vary according to plasma levels of the medication and need to be in the forefront of nurses caring for clients. At therapeutic blood levels, clients may experience gastrointestinal manifestations that often subside with time. Approximately 1/3 of clients taking lithium will experience transient fatigue, headache, confusion, muscle weakness and memory impairment. Polyuria, an extreme increase in urine output, may occur due to the antagonizing effect lithium has on antidiuretic hormone. Lithium may decrease the secretion of thyroid hormone, causing goiter or hypothyroidism. A fine hand tremor may develop and is exacerbated by stress or fatigue. At levels higher than recommended, adverse effects will manifest as muscle hyperirritability, ECG changes, incoordination, ataxia, blurred vision, seizures, significant hypotension and coma, which may progress to death.

Safety Alert

The therapeutic range for lithium is 0.8 mEq/L to 1.2 mEq/L, which is very narrow. Dependent on therapeutic effects desired, the range may increase to up to 1.5 mEq/L, such as during an acute manic episode. Clients’ serum levels can reach toxic levels very quickly. Monitor clients’ serum lithium levels on a regular basis to make sure they remain below 1.5 mEq/L. Observe for manifestations of toxicity, such as muscle hyperirritability, ECG changes, incoordination, ataxia, blurred vision, seizures, significant hypotension and coma, which may progress to death.

Interventions

Interventions for clients taking lithium include monitoring for early, transient adverse effects. It is important to differentiate these from toxic effects by monitoring lithium blood levels. It is also important to monitor the client’s fluid intake and output and to watch for manifestations of electrolyte imbalance. Watch for manifestations of hypothyroidism, such as lethargy, low heart rate, and decreased body temperature. Also, plan to monitor thyroid function tests once a year. For clients who develop a tremor, monitor for coarsening of the tremor, which could indicate toxicity to lithium. Monitor serum sodium levels, since decreased levels may cause lithium toxicity. It is important to recognize manifestations that may indicate toxicity to prevent more severe toxic effects. Early manifestations of toxicity include nausea and muscle weakness. Monitor the kidney function throughout treatment, since renal failure can also occur as a result of lithium toxicity.

Administration

Give lithium with milk or meals to prevent adverse gastrointestinal effects. And, as always, make sure clients swallow sustained-release tablets whole and do not crush or chew them.

Client Instructions

If clients feel drowsy, tell them not to drive or perform hazardous tasks. They should plan to avoid caffeine and stressors, which can increase the risk for tremors. Advise them to notify the provider of worsening tremors, which can indicate lithium toxicity. Tell clients to report manifestations of hypothyroidism, such as fatigue, lethargy, and an inability to tolerate cold temperatures. It’s also very important to instruct clients to recognize manifestations of lithium toxicity. Instruct clients to take lithium with food to minimize gastrointestinal side effects. Instruct to inform the provider if gastrointestinal effects do not subside or become worse.

Safety Alert

Hyponatremia can decrease the excretion of lithium, increasing its serum levels to near or above toxic levels. Instruct clients to avoid becoming dehydrated by drinking 2 L to 3 L of fluid each day. Make sure they consume adequate amounts of dietary sodium to allow for the proper excretion of lithium.

Contraindications and Precautions

Lithium is a pregnancy risk medication (teratogenic) and may cause fetal heart defects if pregnant clients take it during their first trimester. Clients should not take it during lactation or if they have severe renal insufficiency or moderate to severe cardiac disorders. Clients who are dehydrated, who have a low serum sodium level, who are taking diuretics, or who must be on a low-salt diet should not take lithium. Also, clients with a history of angioedema (swelling around the lips and mouth caused by taking ACE inhibitors) should not take lithium. Take precautions for clients who take lithium and have a history of thyroid or seizure disorders, diabetes mellitus, problems with urinary retention, or suicidal ideation. Use caution with older adults, who are more likely to have other health problems and who may take multiple medications for other disorders.

Interactions

Lithium interacts with many different medications. These include nonsteroidal anti-inflammatory medications, also called NSAIDs, with the exception of aspirin. Tetracyclines, diuretics, methyldopa, and probenecid increase the risk for lithium toxicity. Phenothiazine antipsychotics, such as haloperidol, increase the risk for dyskinesias and urinary retention. Also, ACE inhibitors, which are antihypertensive medications, may increase lithium levels, causing toxicity.