Mood Stabilizers

The first mood stabilizer was Lithium Carbonate. This was the treatment of choice for mood swings and remains the treatment of choice for Bipolar I, manic depressive disorder. The principle concern in use of Lithium is that it can cause kidney disease. To this end one checks Creatine and Glomerular Filtration rate before starting the medication and then again at 3 months and thereafter every 6 to 12 months.  Lithium can also cause thyroid disorder and this also needs to be assess before starting treatment and thereafter at 3 months and then every 6 to 12 months.  Lithium levels are established with safety and efficacy being in the .5 to 1.5 range depending on laboratory normals.  I give these figures here to say that if one is using the lithium predominantly for prevention then the dosage should be established where the lithium level is around .5 however if a person is acutely manic and a risk to self and others the lithium level will be established at around 1.5.  This said Lithium can also be used in the low dose range 300 to 600 mg to augment other mood disorder treatments.
Tegretol or Carbamezapine was the next medication found to be a mood stabilizer. This was used as the second line of choice in Bipolar I, manic depressive disorder.  It's also an antiseizure medication and specific therapy for temporal lobe epilepsy. Clinically I have seen it's benefit with anger management as well.  Bipolar II is a tenuated form of Bipolar I and was previously called 'cyclothymic' or 'dysthymic' disorders.  It can benefit from the use of carbamezapine especially if the 'irritability' component is outright anger.  That said it's use in Asian populations has to be considered in terms of cost/benefit because of the risk for a subset with HLA-B-1502 Allele developing fatal dematitis.  If use is considered in asian population then test for HLA-B-1502 is indicated first.  Aplastic anemia and agranulocytosis blood disorders are a risk so cbc with special attention to wbc is indicated.  The CBC should be taken before starting mediation. There are alot of serious reactions possible including hepatitis, pancreatitis, suicidality, water intoxication and arrythmias.  Therefore CBC, wbc, liver enzymes and EKG are to be considered before starting and when the patient is on the medication especially with increasing dosage.
Valproic Acid was the mood stabilizer most promoted for Bipolar II and so called 'rapid cycling' disorders.  The difficulty with these variants of bipolar is there is a lack of specificity and interrater reliability. Clinically it is also common for mood swings and complaints of them to occur in patients with addiction. When the clinician commonly fails to take an intensive alcohol and drug history or the patient is not forthcoming, the patient is at risk for having liver disease missed. There are been cases of sudden death with valproic in patients with liver disease.  Liver screening is indicated. Adverse reactions noted in Eppocrates include coma, encephalopathy, aplastic anemia in addition to the concerns that can occur with Carbamezapine.  My tendency is to not use valproic acid in the drug and alcohol populations which I treat where liver disease must be considered as most likely. That said I have seen other patients whose lives have been much benefitted from the use of valproic acid.
It should further be considered that the dosages used in psychiatric treatment are often far less than these medications have been used at for seizure disorders for which carbamezapine and valproic acid were first used for.
Gabapentin and Topamax (topiramate) are other mood stabilizers which have benefit in psychiatric disorders.  Topamax must be considered carefully as it can be associated with kidney disease and it can cause reversible with stopping the med unusual localized anaesthesias.  Topamax is often appreciated as it is also associated with weight loss.
Lamotrigine is the latest of the mood stabilizer medications and has been shown to be very beneficial in some cases.  It tends not to be a first choice but has been very robust in its efficacy further it has benefit in augmenting other therapies. It has a side effect profile similiar to valproic acid with sudden death and aseptic meningitis.  I can't say I've heard of any of these complications and my patients have benefitted as greatly from this medication as from the apparently safer carbamezapine, gabapentin and topiramate.
Oddly Dilantin, another anti seizure medication doesn't appear to have any benefit in treating mood disorders.
Clonazepam, the long acting diazepam (valium)  and lorazepam the short acting anxiety medication are interestingly 'anti seizure medications.  Given this it's not surprising that other anti seizure medications have benefit in anxiety disorder, irritability disorders and the bipolar disorders.
Increasingly atypical antipsychotic medications such as olanzepine, rispiridol, seroquel (quitiapine) and the newer abilify and zeldox have become mainstays of use for 'mood stabilization.'
There is always ongoing conflict with pharmaceutical companies and the regulating bodies around this issue of 'off label' and 'on label' usage. These latter drugs were developed at 'anti schizophrenia' drugs but as schizophrenia commonly has a major anxiety component with some schizophrenias overlapping with mood disorders clinicians naturally use these medications with complex cases and find them beneficial.  Medicine is art and science and psychiatry is very much so. The pharmaceutical companies develop medications that are profoundly beneficial for patients and the government regulatory bodies do their best to regulate their usage to reduce the risk to the population.  The politics of this are often difficult for patients who don't understand that very often a safe and very helpful medication for them specifically is politically and legally suddenly in question because of the means whereby it came to market.  Ironically if a pharmaceutical medication of proven benefit says that its good for anxiety and depression where it's only got 'on label' promotion for depression the company can be sued for millions.  I say ironically because the so called 'health food" "alternative medicines" can make no end of unproven and mostly false claims without any legal consequences.  Further much of the information that is being given to patients by pharmacists is not relevant to them as the doctor chooses a medication and dosage which is specific and considered in the light of their clinical experience.  Because of problems of the courts and the FDA more often than not the side effects given for medications are 'medical disclaimers'.  One case is a million risk is shown beside a one in 100 risk side effect without any explanation given to patients.