Once upon a time there were jokes circulating about putting Prozac (fluoxetine) in the drinking water.
The idea was that the modern antidepressants were indicated for most people living in today’s society, and that these drugs were completely safe to use.
Now, these same drugs have so many warnings that they have become increasingly difficult to use in treating the common maladies of depression and anxiety.
The earliest scuttlebutt about Prozac causing suicidal thinking never did go away completely. We were assured that the suicide rate itself did not go up, only thinking about it. Some of that was explained by powerful antidepressants potentially unmasking bipolar illness and causing manic episodes. But a few years later, Paxil (paroxetine) was reported to cause suicidality in adolescents.
Just in the past few months, I was reminded several times about the intricacies of prescribing SSRIs.
A middle aged man on the blood thinner warfarin suddenly developed nosebleeds when his INR shot above the therapeutic range. His psychiatrist had doubled his Prozac two weeks earlier.
An anxious and depressed elderly woman wanted to try an antidepressant, and I gave her a low dose of Lexapro (escitalopram). She told me the following week that she felt tired and listless. I ordered some routine blood taste and her sodium level came back precipitously low. We stopped her Lexapro and she felt better again within a week.
A tall, thin elderly man with Parkinson’s disease and depression wanted to try something for his mood. I searched the literature and prescribed the SSRI with the most data on use in his condition. The following week he felt lightheaded. His blood pressure and pulse were both lower than his baseline, and I ended up cutting his beta blocker in half twice before his vital signs normalized; I had never heard or seen this interaction before.
A middle aged woman with a history of pulmonary emboli had been difficult to regulate on warfarin, and during a recent hospitalization, the doctors had changed her over to the novel anticoagulant Eliquis (apixaban), which doesn’t require any monitoring. When it was time to refill her Zoloft (sertraline), my computer flagged me with a bold, red warning that apixaban and sertraline are a dangerous combination resulting in increased risk for bleeding.
The list of warnings for this class of drug goes on, including effects on pregnancy, heart arrhythmias, seizures, glaucoma, liver disease and diabetes.
Given that their effectiveness is reported to be only marginally better than placebo, I have become increasingly more cautious about prescribing them.
Just this year, though, in Molecular Psychiatry, a new analysis of old data suggests that previous studies had used an ineffective rating system for depression, and that SSRIs are more powerful than we thought.
I remain skeptical. Once bitten, twice shy.