How Long Does Ketamine Work for Depression Relief?

Depression can feel like a heavy weight that never lifts, especially for people who don’t respond to regular treatments like antidepressants or therapy. In recent years, ketamine has been making headlines as a new option for those struggling with treatment-resistant depression. Originally used as an anesthetic, doctors discovered that ketamine can also work as a fast-acting antidepressant, often bringing relief in hours instead of weeks.

But while ketamine may work quickly, many people ask the same question, how long do the effects actually last? 

The answer isn’t always the same for everyone. Some people may feel better for a few days, while others notice improvements that stretch into weeks or even months. 

In this blog, we’ll explore how long ketamine works for depression, what factors influence its effects, and why ongoing treatment plans matter.

Understanding Ketamine Therapy for Depression

In recent years, doctors found that low doses of ketamine can help people with depression that didn’t get better with regular treatments. This is often called treatment-resistant depression. What makes ketamine stand out is how fast it works some patients feel noticeable changes in their mood just within a few hours, especially after an IV infusion or even with a nasal spray in some cases 

In a recent study where patients got three ketamine infusions over 11 days, about 52% of them reached remission meaning their depression eased enough. That’s more than half finding real relief in just a short time.

How Quickly Does Ketamine Start Working?

One of the most unique things about ketamine therapy is how fast it kicks in compared to regular antidepressants. While common medications like SSRIs can take 4 to 6 weeks before you notice a difference, ketamine often begins working within hours.

If you’re getting ketamine through an IV infusion, many people start to feel the first effects about 30–40 minutes after treatment begins. With nasal spray (esketamine, brand name Spravato), it’s usually around the same timeframe, sometimes a bit slower since absorption can vary.

It’s also important to know that ketamine has two different types of effects:

• Immediate psychoactive effects: During and right after treatment, you might feel lightheaded, relaxed, or even a little “floaty.” These feelings usually wear off in 1–2 hours.

• Antidepressant benefits: For many people, mood improvements and relief from depressive thoughts start showing up within a few hours to the next day. These benefits can last several days or longer, depending on the person.

How Long Do the Effects of Ketamine Last?

The big question most people have is not just when ketamine starts working—but also how long the benefits actually last. The answer can be very different depending on whether it’s a single session, a series of treatments, or ongoing maintenance.

After a Single Ketamine Treatment

For many people, the lift in mood after just one infusion or nasal spray session can be felt almost right away. But the effects usually fade within a few days. Some studies show improvement lasting 3 to 7 days, while others suggest that certain patients may feel better for up to two weeks. 

After a Series of Ketamine Treatments

When ketamine is given as part of a treatment plan (often 6–8 sessions over a few weeks), the benefits can last much longer. Many patients report feeling better for several weeks to a few months after completing a series. Clinical research has found that this repeated dosing helps “train” the brain into healthier patterns, making the relief more stable and lasting.

Maintenance and Booster Sessions

Because depression can return, some people benefit from booster or maintenance sessions. These are usually spaced out every few weeks or months depending on individual needs. The idea is not to “restart” treatment each time but to sustain the progress made during the initial series. With regular maintenance, many patients are able to keep their depression under control for the long term.

Conclusion

Ketamine therapy has opened a new door of hope for people struggling with depression, especially those who haven’t found relief through traditional treatments. It works faster than most medications, often within hours, and can provide relief that lasts from a few days to several weeks or months when given in a series. Still, ketamine isn’t a one-time fix. Its benefits are strongest when paired with ongoing care like maintenance sessions, therapy, and lifestyle changes that support mental health.

At Mass Mind Center, we understand that every person’s journey with depression is unique. That’s why our approach goes beyond just the treatment itself. We combine science-backed therapies like ketamine with compassionate, personalized care. Our team takes time to understand your story, guide you through each step of the process, and create a plan that fits your needs not just for today, but for lasting wellness.

If you or someone you love is searching for a new way forward, we’re here to help. At Mass Mind Center, our mission is simple: to bring hope, healing, and real change to those living with depression.