Are there long-term dangers to taking medication?
With the recent press regarding the link between Vioxx and heart disease, and the alleged link between antidepressant medications and suicide, fear of long-term adverse effects has grown, particularly for newer medications. With respect to psychiatric medications, this fear includes the belief that medications is a form of mind control that can have permanent long-term effects on one's personality and mind. This particular idea is categorically false. No medication has that level of control over one's mind. With respect to potential long-term adverse effects of various bipolar agents, however, one should be aware of each agent's particular issues. The most common and/or concerning issue for each is the subject of the following paragraphs. The list is otherwise too long; refer to the package insert for each drug for a complete list.
Lithium
Lithium is the most well known in terms of potential adverse effects. First, it is important to note that blood levels need to be monitored regularly. Lithium has a very narrow therapeutic index--that is, the blood level for minimum effectiveness and the blood level for potential toxicity is fairly narrow. Second, there are three potentially long-term adverse effects of which to be aware and to understand: hypothyroidism, kidney damage, and weight gain. There are a number of risk factors for developing hypothyroidism. THey include having a prior history of thyroid problems, being female, being overweight, having a family history of thyroid problems, having rapid-cycling bipolar disorder, and requiring higher doses of lithium. When hypothyroidism develops as a result of lithium it is generally reversible, unless antibodies to thyroid are present. The best indicator for presence of antibodies is family history. If hypothyroidism occurs, thyroid replacement may be indicated. The most common problem that occurs to the kidney in response to lithium is the inability to concentrate urine and preserve fluid over time. The risk of this is both dose and time dependent. That is, kidney toxicity generally occurs after taking higher doses of lithium for many (ten to fifteen) years. Chronic renal failure can occur at theis time; lithium needs to be discontinued once this has happened. One should avoid taking nonsteroidal anti-inflammatory medications for extended periods of time as these medications increase the blood level of lithium and can also adversely impact the kidneys.Weight gain associated with lithium is a slow onset effect. It occurs for a variety of reasons, including the initial increased thirst associated with lithium, the posibility of hypothyroidism from lithium (which can also cause weight gain), and the effect of lithium itself on metabolism. Risk factors associated with weight gain include being young, overweight, and female. The odds of gaining weight are about 50/50.
Depakote (valproate)
Depakote (valproate) has some immediate and long-term adverse effects. The immediate concern for various blood disorders prompts monitoring of a complete blood count. Thrombocytopenia, a drop in platelets (important in blood clotting), is a not uncommon effect. This is easily reversible by stopping the medication. Hepatitis and pancreatitis can also occur early on in treatment, and for this reason liver function tests should be performed regularly. Women of childbearing age should be cautioned, as Depakote (valproate) is associated with a higher incidence of birth defects. A more common, less dangerous, but more distressing problem is alopecia, or hair loss. This is also reversible with discontinuation of the medication. Weight gain is a potential problem, and Depakote (valproate) may play a role in the development of polycystic ovarian syndrome.
Equetro (carbamazepine)
Although reported infrequently, serious adverse organ system effects have been observed with the use of Equetro (carbamazepine). Early in treatment a rash is possible. Most rashes are benign. Should signs and symptoms of a severe skin reaction such as Stevens-Johnson syndrome appear, Equetro (carbamazepine) should be withdrawn immediately. Blood cell problems are the most well known complications. Both leucopenia (loss of white blood cells) and thrombocytopenia can occur. In addition, the liver can be adversely affected, resulting in hepatitis and jaundice. Equetro (carbamazepine) levels, a complete blood count, and liver function must be monitored throughout treatment in order to detect as early as possible signs and symptoms of a possible blood or liver problem. Equetro (carbamazepine) should be discontinued if any evidence of a significant problem appears. Long-term toxicity studies in rats have indicated a potential carcinogenic risk; however, no evidence exists that this medication is carcinogenic in humans. In women of childbearing potential, Equetro (carbamazepine) should be avoided whenever possible or prescribed as monotherapy because the incidence of congenital abnormalities in the offspring of women treated with more than one anticonvulsant is greater.
Atypical Antipsychotic Medications
Although the FDA treats the atypical antipsychotics as a class in terms of side effect profiles, all coming with the same warnings on their package inserts, they do not all demonstrate the same adverse effects equally. The most concerning class effect is the development of metabolic syndrome, which is characterized by a number of metabolic changes, including weight gain and elevated cholesterol, triglycerides, and fasting blood sugars. Some patients have gone on to develop diabetes. A few have developed diabetic ketoacidosis, a medical emergancy stemming from extremely high blood sugars. Not all of the atypical antipsychotics appear to cause this problem to the same degree. The two worst offenders Clozaril (clozapine) and Zyprexa (olanzapine). This is unfortunate, because Clozaril (clozapine) is the most effective antipsychotic on the market, and many clinicians swear by Zyprexa (olanzapine) as being the second most effective and perhaps best-tolerated agent. In the middle are Risperdal (risperidone) and Seroquel (quetiapine). Geodon (ziprasidone) and Abilify (aripiprazole) appear to have no effect on the development of metabolic syndrome though both have been known to cause weight gain to a lesser degree than the others. All of these medications have been known to lead to cerebrovascular events in the elderly, and so their use in this population should be minimized. They also appear to increase the rate of mortality from all conditions in this population for unknown reasons. Finally, while the development of extrapyramidal side effects and tardive dyskinesia is greatly reduced in this class compared to the older typical antipsychotics, it is not nonexistent. Again, it appears some are more likely than others to cause extrapyramidal problems, particularly Risperdal (risperidone). Risperdal (rsiperidone) also can elevate prolactin, which has a number of adverse consequences, including breast growth, lactation, and decreased libido.
Selective Serotonin Reuptake Inhibitors (SSRIs)
SSRIs have been on the market since the introduction of Prozac in the late 1980's. Numerous studies have attempted to link them to long-term dangers such as cancer or other medical conditions aside from their psychological effects. None of these studies has yet held up to any scrutiny. All of the studies linking SSRIs to suicidal behavior analyze data at the beginning of treatment and most likely represent an unidentified side effect that can be associated with suicide behavior. Such side effects could be increasing anxiety and insomnia or an extrapyramidal side effect that causes patients to become uncomfortably restless (akathisia). Another factor that may be involved is the improvement in energy to act on suicidal desires. This is why close monitoring during the initial phase of treatment with these medications is imperative.