Mood Stabilizers

Types and differences of mood stabilizers

Lithium was the first mood stabilizer approved for the treatment of bipolar disorder and it is often used for mania. According to the National Mental Health Association (NMHA), it is effective in controlling mania in 60 percent of patients with this condition. Lithium is available in tablet, capsule and liquid form under many brand names, including:

• Cibalith-S
• Eskalith
• Lithane
• Lithobid
• Lithonate
• Lithotabs

Many anticonvulsant medications are also mood stabilizers. Valproate is also considered a first-line agent and may be more effective than lithium in the treatment of mixed episode (episodes with features of both mania and depression) or rapid cycling (four or more episodes per year) bipolar disorder, according to the National Alliance on Mental Illness (NAMI). The generic and brand names for anticonvulsant mood stabilizers include:

Indications for mood stabilizers

Although they are predominantly used in the treatment of bipolar disorder, mood stabilizers may be prescribed for a variety of other conditions, including:

• Cyclothymia. A milder mood disorder characterized by frequent lower-grade mood swings.
• Borderline personality disorder (BPD). Because of their effectiveness in treating aggression and impulse control, mood stabilizers may be used in the treatment of BPD.
• Mood instability due to other causes. Patients with other conditions that may cause mood problems may be prescribed mood stabilizers as adjunct medications.

Contraindications for mood stabilizers

Lithium is not generally prescribed for patients with kidney conditions or certain heart conditions, such as some arrhythmias (irregular heartbeats). Patients with hypothyroidism (underactive thyroid) are only treated with lithium if their thyroid disease is adequately treated and monitored. Lithium may make psoriasis (a skin disease characterized by a rash covered with silvery flakes) worse. If this happens, the medication may be discontinued.

Anticonvulsant mood stabilizers are not typically prescribed in patients with liver disease. Some are not prescribed in patients with certain blood disorders (e.g., low platelet count). Others may be prescribed with caution and under close monitoring in these patients. Alcoholism may increase the risk of certain blood conditions (e.g., low sodium levels) in patients taking anticonvulsant mood stabilizers.

Potential side effects of mood stabilizers

Most side effects of mood stabilizers are transient, meaning they get better or go away after a few weeks, but some persist. They are generally reversible after the medication is discontinued. Common side effects include:

• Gastrointestinal complaints (e.g., nausea, vomiting, diarrhea). A very common side effect that generally improves if the medication is taken with meals.
• Fine tremor. Shakiness or unsteadiness, particularly of the hands. This tends to get better when the medication dosage is reduced.
• Rash. Many mood stabilizers may cause a rash or acne. Medication may be discontinued depending on the type of mood stabilizer used and the severity of the rash. For instance, the anticonvulsants carbamazepine and lamotrigine are often discontinued if a rash occurs, because rashes can become severe or progress to Stevens-Johnson syndrome, a potentially fatal skin disease.
• Changes in blood chemistry. Most mood stabilizers require frequent blood tests to monitor chemical and compositional levels (e.g., calcium levels, white blood cell count, red blood cell count). Most of these changes are harmless, but some can be quite dangerous. Valproate can reduce the ability of the blood to clot in some patients. In rare cases, carbamazepine can result in significant and dangerous drops in levels of white or red blood cells.

Some side effects of lithium include:

• Headache and back pain
• Fatigue
• Weight gain
• Hair thinning and loss
• Increased urination and thirst
• Memory impairment
• Hypothyroidism (underactive thyroid)
• Osteoporosis (deterioration of bone)
• Hypertension (high blood pressure)
• Progressive deterioration of the kidney (rare)

Other side effects of anticonvulsant mood stabilizers include:

• Drowsiness
• Weight gain
• Hair loss
• Dizziness
• Lack of coordination
• Blurred vision

Drug or other interactions

Many medications can interact with mood stabilizers. Lithium in particular can interact dangerously with other medications. Lithium has a narrow therapeutic window, which means its effective dose is very close to its toxic dose.

A number of commonly used medications can cause lithium to build to dangerous levels. These include over-the-counter medications such as nonsteroidal anti-inflammatory drugs as well as diuretics and ACE inhibitors. By contrast, many respiratory drugs may reduce the levels of lithium in the system, resulting in lowered efficacy. Lithium may increase the effects of certain muscle relaxants.

Anticonvulsant mood stabilizers may be affected by several medications, as well. Some (e.g., carbamazepine, oxcarbazepine) may reduce the effectiveness of many medications, including oral contraceptives. This makes it necessary for women of child-bearing age to use other forms of birth control when taking certain mood stabilizers. Valproate may increase the effectiveness of many medications, including anticoagulants (drugs that help prevent the blood from clotting) and other mood stabilizers. Certain antibiotics may increase the levels of some anticonvulsants, potentially to toxic levels.

Symptoms of mood stabilizer overdose

Because lithium levels required for therapeutic effectiveness are very close to toxic levels, overdose is a serious risk. Intake of plenty of water helps prevent toxicity. Signs and symptoms of overdose require immediate medical attention and discontinuation of lithium. In many cases, dialysis is required for several weeks.

Symptoms of mild to moderate lithium overdose include:

• Vomiting
• Abdominal pain
• Dry mouth
• Lack of coordination
• Dizziness
• Slurred speech
• Rapid, involuntary eye movements (nystagmus)
• Lethargy or excitement
• Muscle weakness

Symptoms of moderate to severe lithium overdose include:

• Loss of appetite (anorexia)
• Persistent nausea and vomiting
• Blurred vision
• Visible muscle twitching
• Rapid, abnormal limb movements
• Seizures
• Delirium
• Fainting
• Stupor
• Hypotension (low blood pressure)
• Cardiac arrhythmias (irregular heart beat)
• Coma

Overdose of anticonvulsant mood stabilizers is also dangerous and can lead to coma or death. Common symptoms include:

• Nausea
• Vomiting
• Drowsiness
• Confusion
• Over- or underactive reflexes
• Seizures
• Trouble breathing

Pregnancy use issues

Many mood stabilizers increase the risk of birth defects when taken during pregnancy and are often either discontinued or switched to a safer mood stabilizer when a woman is pregnant or trying to become pregnant. However, many pregnancies are unplanned and safer mood stabilizers may not be as effective in some patients.

Because bipolar disorder and other conditions treated with mood stabilizers create their own risks to newborns, it may not be practical to discontinue treatment or change to a new, possibly less effective medication. Ultimately, the physician will weigh the risks to the fetus against the risks posed by the condition. Women who are pregnant or may become pregnant and women who intend to breastfeed should consult a physician before taking mood stabilizers.

Lithium poses a risk of heart defects in the fetus, but these risks may be lower than other medications that may have other birth defect risks or may not be as effective. However, lithium’s effective dosage is close to its toxicity level. Pregnant women who are taking lithium should keep themselves well hydrated, which will help prevent lithium toxicity in the fetus, according to the National Alliance on Mental Illness (NAMI).

Careful monitoring of lithium levels in the blood is important for all patients taking lithium (and other mood stabilizers), but it is especially critical for pregnant women.

Lithium secretes into breast milk and may cause significant damage to the developing kidneys of an infant. It is not recommended for women who are breastfeeding. Women who require lithium following childbirth are recommended to use an alternative to breastfeeding, such as bottle feeding with infant formulas.

Valproate and carbamazepine have been associated with a variety of problems, including nerve conditions and developmental delay. Children exposed to these anticonvulsant mood stabilizers in the womb may display low sugar levels in the blood (hypoglycemia) and liver dysfunction, among other problems. These two medications are considered safe during breastfeeding, though some adverse effects may occur. The bloodwork of an infant nursing from a mother treated with valproate or carbamazepine must be monitored closely. The use of oxcarbazepine, a derivative of carbamazepine, requires further study.

Lamotrigine and topiramate appear to be safe during pregnancy and breastfeeding. No problems in infants exposed to these medications in the womb or through breast milk have been discovered. However, both of these medications are excreted in breast milk and lamotrigine levels in infants can be high.

Child use issues

Bipolar disorder in children and adolescents is typically treated with lithium, though valproate or carbamazepine may also be used. However, valproate requires careful monitoring in girls. It has been associated with adverse hormone changes in teenage girls and the development of polycystic ovary syndrome (cysts forming in the ovary) in women who began valproate therapy before the age of 20 years.

Elderly use issues

Although dosages for elderly patients may be lower, treatment and response to mood stabilizers is essentially the same in older adults as in younger adults. However, elderly patients may not tolerate the side effects of mood stabilizers as well and may be more prone to toxicity.