Long-Term Effects of Antidepressants

Do you worry about the effects of long-term use of antidepressants? They're among the most commonly prescribed drugs in the United States, and they're often prescribed for long-term use. But is it safe to use antidepressants for years on end?

While this class of medications is named after a single condition, they're used to treat a wide variety of illnesses other than major depressive disorder, including:

Many of these conditions are chronic or can return if you go off the medication. That means a lot of people take them for years, and that leads to concerns about the long-term side effects.

In spite of how popular these drugs are, we're just learning what those long-term effects may be. Extended studies are rarely done before a drug gains approval, so a drug can be around for a long time before we start to see what can happen after years of continuous use.

Fortunately, the body of literature on the long-term use of antidepressants is growing, and we're gaining a better understanding of their impact on us.

Antidepressants and Your Brain

Before delving into the research, let's look at how antidepressants work. Antidepressants come in several forms. They are:

In your brain, information—including emotion—moves from one neuron (brain cell) to another via chemical messengers called neurotransmitters.

Think of neurotransmitters as mailbox keys. Each one unlocks certain receptors (chemical "locks") on neurons in order to allow the message to keep traveling.

In the diseases and conditions listed above, as well as many others, something is messed up with the neurotransmitters—usually serotonin and/or norepinephrine, and possibly dopamine and/or a few others. It may be that there's simply not enough. In some cases, the brain may not use it efficiently, or the problem could lie with the receptors.

Regardless of the specific cause of the problem, the result is the same: neurotransmitter dysregulation. Going back to our metaphor, the mail isn't getting to the right mailbox, so messages aren't being delivered.

Antidepressants change how your neurotransmitters function, making more available so that when a message comes along, it can be properly delivered. This is achieved by slowing down a process called reuptake, which is essentially a clean-up/recycling process. Once the messages are flowing more like they should, your brain works better and the symptoms related to the slow-down diminish or go away.

However, the brain is a complex environment, and each neurotransmitter has a lot of different jobs.

Increasing the available neurotransmitters may have the desired effect of alleviating your depression, lowering your neuropathic pain, or helping you think straight, but it can also lead to all kinds of unwanted effects.

The potential side effects of antidepressants are many, and they can range from mildly annoying to debilitating and even life-threatening. Beyond that, there's the issue of antidepressants becoming less effective over time.

As we've learned more about the long-term side effects, some of the top concerns that have emerged have to do with weight gain and diabetes. However, many other side effects can continue long term and can have a negative impact on your quality of life.

Long-Term Effects of Antidepressants: What People Say

In 2016, the medical journal Patient Preference and Adherence published a paper looking at what people taking antidepressants long-term had to say about the side effects that they've seen. Overall, they did say they were less depressed and had a better quality of life because of the drugs, but about 30 percent still said they had moderate or severe depression.

The main side effects they complained about included:

Sexual problems (72 percent), including inability to reach orgasm (65 percent)
Weight gain (65 percent)
Feeling emotionally numb (65 percent)
Not feeling like themselves (54 percent)
Reduced positive feelings (46 percent)
Feeling as if they're addicted (43 percent)
Caring less about other people (36 percent)
Feeling suicidal (36 percent)

Many of the participants wanted more information about the long-term risks of their medication.

About 74 percent of people also mentioned withdrawal symptoms, and said they needed more information and support about going off of antidepressants. (You should never stop taking antidepressants suddenly. Talk to your doctor about the proper way to wean off of them.)

Some people also noted that they'd had to try multiple antidepressants before finding one that worked well for them and was tolerable. However, more than two-thirds of the people questioned said the medication helped them cope with life. About one-fifth said the antidepressants helped them to function well.

Some people also said that if they'd known about the side effects and withdrawal difficulties, they would never have started on the drug at all.

What It Means for You

Before taking an antidepressant, make sure you're familiar with the possible side effects as well as the proper method of going off of them. Know that you may need to try several drugs before finding the best one for you.

While you're on the medication, stay vigilant for side effects and weigh how significant they are versus how much the drug helps you. While you should involve your doctor in any decisions you make regarding antidepressant use, you're the only one who can decide whether the benefits outweigh the drawbacks.

Weight Gain

A 2015 study in The Journal of Clinical Psychiatry suggests that the long-term risk of weight gain from antidepressants that alter serotonin receptors may be significantly higher in women than in men, possibly due to gender differences in how serotonin is used.

Also in 2015, an Australian study noted that people on antidepressants tended to gain more than 3 percent of their body weight each year. Over time, that can really add up.

What it Means for You

Weight gain can have negative effects on your self-esteem as well as your health. Talk to your doctor about how you may be able to improve your diet and/or increase exercise to help keep those extra pounds from piling up.

Blood Sugar & Diabetes

Several studies have noted what appears to be a link between antidepressant use and problems with blood-sugar regulation, including type 2 diabetes.

A systematic review published in a 2013 edition of the journal Diabetes Care examined this relationship to get a better feel for what's going on. They looked at 22 studies, including a couple with more than 4000 participants.

Here's a look at some of the findings that prompted the review:

Antidepressants may worsen blood-sugar control because they can cause significant weight gain.
SSRIs and nortriptyline reportedly worsen blood-sugar control in people with diabetes.
Tricyclic antidepressants cause hyperglycemia (high blood-sugar levels) in humans.
In mice, tricyclic antidepressants cause a condition called hyperinsulinemia, in which the blood contains too much insulin relative to the amount of sugar.

The aim of the review was to determine whether antidepressants raise the risk of diabetes in people who didn't have it when they started on the medications. They concluded that yes, some antidepressants affect blood-sugar regulation and that the drugs could be a risk factor for diabetes. However, the larger and more recent studies they looked at suggested that the risk was small.

They do say, though, that higher doses appear to be linked to a greater risk. Also, in some cases, people who have developed type 2 diabetes while on antidepressants have seen the disease disappear when they went off of the medication.

Researchers also note that people who were diagnosed with diabetes were more likely to be prescribed antidepressants, but the relationship there isn't clear.

What It Means for You

If you're concerned about your diabetes risk or have type 2 diabetes, you may want to talk to your doctor about finding an antidepressant that is less linked to blood-sugar problems. You may also want to test your blood sugars more frequently.

If you have diabetes, your doctor may want to adjust your diabetes medications while you're on antidepressants to make sure your blood-sugar levels are staying in a healthy range. You might also want to focus more on weight loss and exercise, since both of those things play a role in diabetes, and your antidepressant may be causing some weight gain.

Can Antidepressants Make You Depressed?

Can using antidepressants for too long actually make you depressed? Some studies suggest that it might. Two studies published in 2011, from the same research team, noted that people with supposedly treatment-resistant major depressive disorder, who've been on high doses of antidepressants for a long time, often feel better after weaning off of the medication.

Because antidepressants can become less effective over time, as you develop a tolerance for them, symptoms can come back down the road; however, this team doesn't believe that can account for all of the people who develop worse depression while taking the drugs. They hypothesize that the drugs may lead to changes in the brain that actually cause depression.

In these cases, they proposed the term tardive dysphoria to describe the increase in symptoms. "Tardive" means that it comes on late in treatment. "Dysphoria" is a state of depression, dissatisfaction, discomfort, or restlessness.

The researchers call for tardive dysphoria to be studied as a potential side effect of antidepressant use and considered as a possible factor in studies of treatment-resistant depression.

What It Means for You

The study of tardive dysphoria is in the earliest stages. If your depression has gotten worse in spite of being on antidepressants, talk to your doctor about tardive dysphoria as well as other possible causes before deciding whether to go off of your medication. Also, remember that you need to wean off of the drugs properly.

It's easy to jump to conclusions with things like this, but keep in mind that we don't even know for certain that tardive dysphoria is a problem with antidepressants. Be smart and cautious as you make important medical decisions and involve your medical team.

A Word From Verywell

As all drugs do, antidepressants have lists of potential pros and cons. Treatment is a balancing act, with you and your doctor(s) weighing the good against the bad and deciding what the next move should be.

Starting a new drug is a big decision, and so is continuing treatment long-term or opting to discontinue. Make sure you're well informed at every step and getting professional advice. In the end, it's all about making you feel better.

Sources:

Barnard K, Peveler RC, Hold, RIG. Antidepressant medication as a risk factor for tye 2 diabetes and impaired glucose regulation: systematic review. Diabetes Care. 2013 Oct; 36(10): 3337–3345. doi: 10.2337/dc13-0560.

Cartwright C, Gibson K, Read J, Cowan O, Dehar T. Long-term antidepressant use: patient perspectives of benefits and adverse effects. Patient preferences and adherence. 2016 Jul 28;10:1401-7. doi: 10.2147/PPA.S110632.

El-Mallakh RS, Gao Y, Briscoe BT, Roberts RJ. Antidepressant-induced tardive dysphoria. Psychotherapy and psychosomatics. 2011;80(1):57-9. doi: 10.1159/000316799.

El-Mallakh RS, Gao Y, Roberts RJ. Tardive dysphoria: the role of long term antidepressant use in inducing chronic depression. Medical hypotheses. 2011 Jun;76(6):769-73. doi: 10.1016/j.mehy.2011.01.020.

Noordam R, Aarts N, Tiemeier H, et al. Sex-specific association between antidepressant use and body weight in a population-based study in older adults. Journal of clinical psychiatry. 2015 Jun;76(6):e745-51. doi: 10.4088/JCP.13m08896.

Paige E, Korda R, Kemp-Casey A, et al. A record linkage study of antidepressant medication use and weight change in Australian adults. The Australian and New Zealand journal of psychiatry. 2015 Nov;49(11):1029-39. doi: 10.1177/0004867415607365.