Antidepressant Side Effects: What You Need to Know Before Starting Treatment

When you start an antidepressant, a medication used to treat depression, anxiety, and other mood disorders by balancing brain chemicals. Also known as antidepressive agents, these drugs can change how you feel—but they also come with side effects that many people aren’t prepared for. Not everyone gets them, and not all side effects are bad, but knowing what’s normal versus what’s dangerous can make all the difference.

SSRIs, a common class of antidepressants that increase serotonin levels in the brain. Also known as selective serotonin reuptake inhibitors, they include drugs like sertraline and fluoxetine. These are often the first choice because they’re generally safer than older options, but they still cause nausea, sleep changes, and sexual problems in up to half of users. Then there’s SNRIs, another group that affects both serotonin and norepinephrine. Also known as serotonin-norepinephrine reuptake inhibitors, like venlafaxine and duloxetine. They can raise blood pressure and cause more dry mouth or dizziness. And if you’ve ever stopped an antidepressant cold turkey? That’s where antidepressant withdrawal, a set of physical and emotional symptoms that can happen when stopping these drugs too quickly. Also known as discontinuation syndrome, it’s not addiction—but it feels awful. Dizziness, electric shock sensations, and flu-like symptoms aren’t rare—they’re expected if you don’t taper slowly.

These drugs don’t work in a vacuum. They interact with painkillers, herbal supplements, even grapefruit juice. Some people don’t realize their headaches or insomnia are linked to a new pill they started three weeks ago. And while weight gain or low libido might seem like small trade-offs, they’re the main reasons people quit—sometimes without telling their doctor. The good news? Most side effects fade after a few weeks. The better news? There are ways to manage them that don’t involve switching meds. You can adjust timing, add a short-term fix, or tweak your routine. What you’ll find here aren’t just lists of symptoms—you’ll see real strategies from people who’ve been there, backed by the same science doctors use.