SIDE EFFECTS:
Ask the Pharmacist: Archives
Q: What is the difference between Prozac and Zoloft in terms of
how they workand side effects they cause? What is the likelihood of an increase in migraines or seizures among people taking
either of these drugs?
Harold J. DeMonaco, M.S. is the Director of Drug Therapy Management and theChair of the Human
Research Committee at the Massachusetts General Hospital. He is an author of over twenty publications in the pharmacy and
medical literature and routinely reviews manuscript submissions for eight medical journals.
A:
Prozac and Zoloft
are two members of a class of antidepressants known as selective serotonin reuptake inhibitors (SSRIs). Other members of this class of drugs are Paxil, Luvox and Celexa.
All have the same basic mechanism of action but all have slight
differences in the way they work, and, as a result, difference in the side effects they produce. All are equally effective
in the treatment of depression.
Here is the information from the package inserts for each of the drugs.
The number
represents the percentage of patients who experienced the
side effect during clinical trials.
Side Effect
Prozac Luvox Paxil Zoloft Celexa
Nausea......................21.1
40 25.7 26 21
Headache..................20.3 22 17.6 20
Not reported
Nervousness.............14.9 12
5.2 3.4 Not reported
Sedation....................11.6
22 23.3 13 18
Insomnia....................13.8
21 13.3 16 15
Dry Mouth....................9.5
14 18.1 16 20
Diarrhea....................12.3 11
11.6 18 8
Weakness/Fatigue......4.2
14 15.0 11 5
Anxiety/Agitation.........9.4
5 5.0 5.6 4
Sexual
Dysfunction......1.9 8 12.9
16 6
Loss of appetite.......... 8.7
6 6.4 2.8 4
The
incidence of seizures with the SSRIs is so low that it is impossible to
distinguish among the members of the class. Overall,
the incidence of seizures with all antidepressants is less than 1 percent.
I know of no increased risk of migraine
associated with the use of any SSRI antidepressant. Migraine is frequently seen in patients with depression, however.
January
23, 2001
