SSRIs and SNRIs

At a glance

Compared with waiting

Large difference compared with waiting, in a combined analysis of 101 trials.

Compared with other treatments

Better than a pill placebo, by a small amount on average. In a review of 24 trials, people on an SSRI were about 1.65 times as likely to respond as people on placebo.

Does it last

Staying on the medicine lowers the chance of relapse. Across anxiety disorders, about 36 in 100 relapsed within a year after switching to placebo, compared with 16 in 100 who stayed on the medicine.

What it takes

A daily tablet, usually for months, prescribed and reviewed by a doctor. Trials usually measure results after a few months.

What they are

SSRIs (selective serotonin reuptake inhibitors) and SNRIs (serotonin and noradrenaline reuptake inhibitors) are antidepressant medicines. They are also used for anxiety. Common examples are sertraline, escitalopram, paroxetine, fluvoxamine and venlafaxine.

You take them every day, not just before a stressful event. Canada’s guideline lists escitalopram, fluvoxamine, paroxetine, sertraline and venlafaxine among its first-choice medicines for social anxiety disorder. A doctor decides which medicine and dose suit you.

What people report

On Reddit, views are split. One widely upvoted post described social anxiety that had “nearly vanished” on escitalopram, and regret at waiting so long because of negative stories online. Replies to the same post described the opposite: feeling numb, flat or worse. In discussions of antidepressants, people often talk about emotional flattening, sleep problems and withdrawal “brain zaps”.

These are reports from people, not trial results. They show that experiences vary a lot.

What the trials show

• They beat placebo. A study that combined 101 trials found SSRIs and SNRIs were one of only two treatments that clearly beat a placebo. The other was individual CBT. Compared with placebo, the difference was small.
• Response. A Cochrane review of medicines for social anxiety found people on an SSRI were about 1.65 times as likely to respond as people on placebo. The reviewers rated the quality of this evidence as very low.
• They prevent relapse while you take them. SSRIs were the only class of medicine with moderate-quality evidence that they reduce relapse.
• Stopping raises the risk of relapse. A study combining 28 trials followed people who had improved on an antidepressant. Among those switched to placebo, 36.4% relapsed within a year. Among those who stayed on the medicine, 16.4% did. This covered several anxiety disorders, not only social anxiety.

Medication or therapy?

There is no single ranking. The answer depends on what the treatments are compared with.

• Compared with their own starting point, medicines look stronger. A study that combined 234 trials found larger before-and-after changes with medicines than with therapies. But this kind of comparison includes the placebo effect. In the same study, people taking dummy pills also improved a lot from where they started.
• Compared with a placebo or with waiting, the combined analysis of 101 trials found individual CBT made for social anxiety had the largest effect.
• Head to head, in a UK trial of 60 people, cognitive therapy beat the SSRI fluoxetine, and the gap held for a year.

Many people use both. A medicine can make it easier to start therapy. The UK guideline (NICE) recommends individual CBT first, and an SSRI if you prefer medicine.

Side effects

Common side effects include nausea, stomach upset, sweating, shaking and sexual problems, such as lower sex drive or delayed orgasm. These are listed on the MedlinePlus sertraline page. Some people feel emotionally flat or “blunted”. A UK study of people’s own accounts described this in detail.

Young people: antidepressants carry a warning that they can raise the risk of suicidal thoughts in people under 24, especially in the first months or after a dose change. If you have thoughts of harming yourself, contact your doctor or a crisis line straight away.

Tell your doctor about any that bother you. Changing the dose or the medicine often helps.

Stopping

Never stop or change an SSRI or SNRI without talking to your doctor. Stopping suddenly can cause withdrawal symptoms such as dizziness, nausea, headaches, mood changes and trouble sleeping. Symptoms of social anxiety also often come back. Your doctor can plan a slow reduction when the time is right.

Talking to your doctor has tips for raising medication.