Intravenous ketamine is emerging as a critical intervention for treatment-resistant depression (TRD) in Singapore, offering rapid relief where traditional antidepressants fail. According to the Institute of Mental Health (IMH), the treatment targets glutamate receptors to repair brain cell connections, providing a faster alternative to standard medications that often require weeks to take effect. Clinical data from IMH shows that over half of treated patients experience significant improvements in mood and energy levels.
Clinical Efficacy of Intravenous Ketamine for Depression
Unlike traditional selective serotonin reuptake inhibitors (SSRIs), which regulate serotonin over several weeks, ketamine acts on glutamate receptors. This mechanism allows the brain to “reset” and adapt to more positive thought patterns, according to Goh Shih Ee, a consultant psychiatrist and head of the neurostimulation service at IMH.
Data from IMH indicates that between late 2024 and mid-2026, over half of 13 patients responded to intravenous ketamine. This aligns with global studies reporting response rates between 35.7 per cent and 68 per cent. Goh notes that patients often report improvements after just two to three sessions. This is a sharp contrast to conventional antidepressants, which typically require four to six weeks of consistent use before patients notice a shift in their condition.
Did you know? While ketamine is often associated with recreational use, medical practitioners administer it in controlled, sub-anaesthetic doses. These doses are too low to induce general anaesthesia but high enough to achieve therapeutic, rapid-acting antidepressant effects.
Comparing Ketamine to ECT and TMS
For patients with major depressive disorder (MDD) who do not respond to at least two different medications, doctors consider alternative therapies. These include electroconvulsive therapy (ECT) and transcranial magnetic stimulation (TMS).
| Treatment | Reported Response Rate | Key Considerations |
|---|---|---|
| ECT | about 60 per cent to 80 per cent | Requires general anaesthesia; risk of memory impairment. |
| TMS | about 20 per cent to over 40 per cent | Uses magnetic pulses to stimulate brain regions. |
| IV Ketamine | 35.7 per cent to 68 per cent | Rapid onset; outpatient delivery; no anaesthesia required. |
Joseph Lim, a 31-year-old patient, underwent 24 sessions of ECT before turning to ketamine. He reported that while ECT provided initial relief, the effects eventually faded. Since starting intravenous ketamine, Lim has completed 52 sessions over two years, noting, “For the first time in five years, I felt that my self-esteem issues were not bothering me.”
Treatment Protocols and Safety Measures
At IMH, intravenous ketamine is delivered in an outpatient setting. A standard acute course involves eight sessions, scheduled twice weekly. Following this, patients may move to a tapering or maintenance schedule, ranging from once a week to once every four weeks, depending on individual progress.
Safety remains a priority, as ketamine is a controlled substance. Goh emphasizes that the risk of addiction is mitigated by the use of low, clinically indicated doses administered in a supervised hospital environment. Furthermore, the service is limited to psychiatrists who have completed specialized training. In addition to the intravenous service, the Health Sciences Authority approved a nasal spray version (Spravato) in 2020, which is also available at IMH for use alongside oral antidepressants.
Frequently Asked Questions
Who is eligible for intravenous ketamine treatment?
It is primarily intended for patients with treatment-resistant depression who have not seen improvement after trying multiple antidepressant medications or other therapies like ECT and TMS.
How does the IV treatment differ from the nasal spray?
While both provide rapid symptom relief, the intravenous method allows doctors to adjust doses more precisely and avoids the altered taste side effect associated with the nasal spray.
Are there side effects?
Some patients may experience transient dissociative effects, such as visual sensations, which typically do not last long after the treatment session concludes.
If you or someone you know is struggling with mental health, help is available. You can contact the National Mindline at 1771 or the Samaritans of Singapore at 1-767 for 24-hour support.
Have you or a loved one explored advanced treatments for depression? Share your experiences or questions in the comments section below to help foster a supportive community.
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