”These antidepressants are often prescribed “off-label,” says David Diaz, an assistant professor of clinical psychiatry at Indiana University School of Medicine. Meaning they’re being used in a way not specified in the [U.S.] Food and Drug Administration-approved packaging label. But “just because the medication is off-label does not mean it's being used experimentally,” Diaz says. “In many cases, it's the community standard.”
With 118 million prescriptions of antidepressants written a year, it is the third most common drug class prescribed in this country. It is estimated that one in five prescriptions are written off-label. Diaz estimates that one-third or more of antidepressant prescriptions are for off-label uses.
Antidepressants and Chronic Pain
Tricyclic antidepressants (TCAs) are older antidepressants that have fallen into disfavor because of the high doses it requires for effective action against depression. Often these doses induced sleepiness and fatigue. But TCAs are being used for another purpose: to reduce chronic pain in sufferers.
The funny thing is that researchers don’t know exactly how these drugs work but there is a theory. The theory posits that TCAs don’t block the pain at the receptor level, but that it modulates the way your brain processes the pain signal.
So this class of drugs has been found to be effective in treating neuropathic pain, pain typically caused by nerve damage or other nerve problems. Neuropathic pain is often unresponsive to traditional painkillers.
Ironically, these TCAs can help with diabetics. What do TCAs have to do with diabetes? They are often prescribed to diabetic patients for their chronic nerve pain, peripheral neuropathy. Peripheral nerves are those that lie outside of the brain and spinal cord. It is these nerves that are damaged, and diabetes is the most common cause of peripheral neuropathy. Other causes include viral infections such as the shingles, physical injury to the nerves or side effects of certain medications.
Signs of peripheral neuropathy include numbness or tingling in the hands, feet, arms and legs, loss of balance and coordination, burning, stabbing or shooting pain in affected areas, and muscle weakness, especially in the feet.
Antidepressants have proven less effective with non-neuropathic pain. But they benefit those with chronic neck or back pain, and fibromyalgia – the most common form of musculoskeletal chronic pain. A selective serotonin and norepinephrine reuptake inhibitor (SNRI) helped cut pain levels by 50 percent after taking the drug for 28 weeks. This use has been FDA approved since 2009.
Multiple sclerosis (MS) affects the nerve pathways of the brain and spinal cord. Another SNRI has been used successfully in MS patients for their symptoms of spasticity, difficulty with balance and coordination, vision, and problems with muscle movements.
Premature Ejaculation
This can be a surprising selection, but it’s true; antidepressants can be a big help for those men with premature ejaculation. This form of sexual dysfunction is number one in the pantheon of male problems and selective serotonin reuptake inhibitors (SSRIs) are the drugs of choice to resolve it.
These SSRIs work by affecting the central nervous system and delaying the triggering mechanism for ejaculation. Dosage of the SSRI coincided with ejaculation delays until the tipping point, when men couldn’t ejaculate. That is the downside of this drug so a patient and doctor need to have a frank discussion of patient expectations and possible side effects.
SSRIs, TCAs and Migraines
These two classes of antidepressants, SSRIs and TCAs, may both be useful for migraine patients who cannot tolerate the standard protocol. These drugs are also good if the patient has concomitant depression or anxiety or any other illness that is responsive to antidepressants. Preliminary studies with fluoxetine, an SSRI, saw a significant decrease in migraines but it is too early in the research process for conclusions.
A TCA known as amitriptyline was deemed one of the most effective medications for migraines. Seventy percent of patients prescribed amitriptyline found acceptable relief, especially if the headache was a tension and migraine headache simultaneously. This drug affects the levels of serotonin and other chemicals in the brain. There is one SNRI, Effexor, that may be helpful in preventing migraines but further studies must be done.
Vasovagal Syncope
Just a fancy way of saying, “fainting.” This fainting is usually caused by standing up quickly, dropping blood pressure, leading to a brief decrease in blood flow to the brain. And fainting. But SSRIs may lower the activity level of the sympathetic nervous system in a way that doesn’t allow for lowered blood pressure in the body. Doctors recommend long-term use of SSRIs for those with frequent fainting spells. The mechanism is not well understood and needs further study.
Women and Incontinence
It is estimated that between four and ten percent of women experience urinary incontinence. And 50 percent of those cases are stress urinary incontinence. This happens when there is an unintentional loss of urine when physical movement or activity, such as coughing or sneezing, puts pressure on your bladder. Women were less likely to have episodes of stress incontinence when taking the antidepressant SNRI duloxetine. This drug is thought to be effective because of certain actions on the central nervous system. It has been theorized that perhaps this SNRI is effective because somehow the pelvic muscles are tightened or strengthened to prevent urine leakage.
Other uses for antidepressants include the possibilities of SNRIs or SSRIs to help relieve hot flashes as well as symptoms of premenstrual dysphoric disorder that is often linked to depression.
These are some surprising uses for antidepressants with which you may not be familiar. So if your family doctor recommends an antidepressant for your illness that is not depression, ask a few questions. Sometimes the best medicine is the most unexpected.