In an earlier entry, I discussed drug interactions and the troubling rise in unintentional drug poisonings. Now, I want to address one particular category of interaction: the potentially fatal condition known as serotonin syndrome.
The widely prescribed antidepressants — selective serotonin reuptake inhibitors (SSRIs) such as Zoloft, Prozac, and Paxil — as well as drugs like Effexor, which inhibit the reuptake of both serotonin and norepinephrine, can cause this dangerous disorder.
Serotonin syndrome is caused by excessive levels in the blood and brain of serotonin, a highly active hormone/neurotransmitter naturally produced in the body. Symptoms of the syndrome include
- Confusion
- Agitation
- Anxiety
- Tremors
- Loss of coordination
- Fever
- Profuse sweating
- Rapid heartbeat
Serotonin syndrome can occur when antidepressant drugs are used alone or in combination with any of a large number of other medications or dietary supplements. In 2002, 7,349 people taking SSRIs reportedly experienced significant toxic effects, and 93 of them died.
These figures are almost surely underestimates because reporting of these ill effects was not mandatory. A large number of other drugs and drug combinations can also trigger the syndrome.
What can you do to avoid the serotonin effect and other dangerous drug combinations? A number of online sites can be used to check for interactions among drugs, and even with foods and alcohol. However, the various sites differ in the interactions they list; and, more importantly, they cannot take into consideration unique features of your health, physical makeup, and history.
Your best bet is to talk with your doctor before adding any new drug or supplement and to make sure your doctors have a complete list of every medication and supplement you are taking. It's also wise to get all of your prescription drugs at the same pharmacy and to check with the pharmacist about any safety issues before he or she fills a new prescription.
