Selective serotonin reuptake inhibitors, or SSRIs, are a class of antidepressants.
While they are called "antidepressants," studies have shown that these medications are
also effective in treating anxiety and obsessive-compulsive disorders as well. Due to
their decreased adverse effects, increased safety, and easy administration, SSRIs have
become the antidepressants of choice for prescribing physicians.
Serotonin is one of many chemical messengers called neurotransmitters -- that are used
by the brain to communicate signals between nerve cells. Serotonin is thought to play a
significant role in several mental disorders, especially depression. SSRIs increase the
availability and amount of serotonin used in the communication process between adjacent
neurons. Currently, there are five SSRIs approved for use in the United States:
citalopram (Celexa), fluoxetine (Prozac), fluvoxamine (Luvox), paroxetine (Paxil), and
sertraline (Zoloft).
SSRIs are usually prescribed to treat unipolar and bipolar major depression,
obsessive-compulsive disorder, and some anxiety disorders such as panic disorder.
Typically it takes 2 to 4 weeks of treatment with SSRIs for a patient to show improvement
in their symptoms. If a patient has not shown some improvement within that time frame,
the dosage should be increased or another medication prescribed. With SSRIs, a maximum
response is usually achieved at minimal dosage levels.
The side effects of the SSRIs are similar and are generally related to dose or else
they disappear with time. Some of the side effects may include gastrointestinal symptoms,
restlessness (especially motor), agitation, headaches, sweating, bruising, and changes in
sleep, appetite and sexual functioning.
The most important drug interaction for SSRIs is with monoamine oxidase inhibitors
(MAOIs). Combining these two drug classes may cause excitement, profuse perspiration,
rigidity, hyperthermia, tachycardia, hypertension, and possibly death. It is recommended
that a patient switching from fluoxetine to an MAOI be given five weeks following
discontinuation in order to allow the fluoxetine to be completely eliminated from the
body. Other SSRIs, such as fluvoxamine, paroxetine, or setraline are cleared more rapidly
from the body, so less time is usually required (one to two weeks) between the
discontinuation of the SSRI and start of the MAOI.
When discontinuing an SSRI, it is often advisable to slowly taper the dosage, even if
the patient has only been on the medicine for a short time. Some SSRIs may cause the
patient to exhibit temporary withdrawal symptoms if stopped suddenly. |
