Ketamine treatment service

Find out about our paid-for ketamine treatment service for depression

Common questions

Please find below frequently asked questions about our service.

Accessing the service

Waiting times can vary throughout the year, on average once we have received a referral for you the appointment for an initial consultation will be booked for within 2 months.

Waiting times for treatment after an initial consultation can range from 1 – 4 weeks depending on the availability of appointments.

We will not be able to see you without a referral from your GP or psychiatrist. Sometime people have found it helpful to take the information leaflet about the service to their doctor.

No. Your referring doctor will remain responsible for your overall care and the prescribing of all other medications including any other antidepressants.

Should you experience acute sickness during your infusion the anaesthetist may prescribe an anti-sickness medication to be given in clinic.

No. The service is set up to provide and manage ketamine treatment. Any other psychiatric care will remain with your current team. We are unable to take on the overall care of patients and will correspond with your referring team about your ketamine treatment.

About Ketamine

For some people, ketamine can work within a few hours. For other people it may take a few treatments before their depression improves. It is not possible to tell who will respond, or how quickly to ketamine.

It is thought that if you do not respond to 3 treatments of ketamine then you are unlikely to see a benefit from any further treatment. Occasionally we recommend a further 3 treatments to help make this judgement.

The dose of ketamine you are prescribed is decided by the ketamine clinic Consultant. Doses are calculated on your weight at 0.5mg/kg and will be reviewed before each treatment. For most people this dose will not change; however, doses may be increased or decreased during your treatment period.

Ketamine is sometimes taken illegally in large, frequent doses. Drug abusers can become addicted to it.

Sometimes people find that if they stop ketamine their depression relapses. This is not the same as addiction. This is reliance.

Sometimes patients taking it for depression find that their depression is no longer controlled despite continuing to have treatment with ketamine. There can be several possible reasons, one of which is that they have developed tolerance to ketamine. This may mean that a treatment break is needed or that it is no longer an effective treatment and therefore will be stopped. Sometimes, the dose can be safely increased. However, it is best to reduce the dose or extend the interval between doses to help maintain the effect.

Sometimes, people find that they think a lot about ketamine and crave it. It is important to notice that this is happening and to be open and honest with the clinical team about this.

We are not aware of reports of anyone who has taken ketamine as prescribed for the treatment of depression and who has become addicted. However, when people use ketamine illegally it is not uncommon for the dose and frequency to escalate.

For comparison, ketamine is much less addictive and dangerous than strong opiates (eg fentanyl, methadone), is probably less addictive and dangerous than tobacco, and has equivalent risks to benzodiazepines.

There is a possibility that a genetic mutation predicts whether patients develop an initial response. However, we do not assess whether you have this mutation. There are no known predictors of a longer duration of response.

Patients over 65 years old may be less likely to respond. Patients with typical biological symptoms of depression (loss of appetite, disturbed sleep, diurnal variation of mood, slowed thinking and movement) may possibly be more likely to respond. People who have been extremely unwell (eg immobile) for a very long time may be less likely to respond.

These predictors have not been confirmed and patients who have been chronically depressed and had partial or equivocal response to conventional antidepressants have also benefitted.

Your treatment

You must not drink alcohol on the night before and day you take ketamine and for 24 hours afterwards.

If possible, you should avoid drinking alcohol completely while you are taking ketamine. This is because alcohol may reduce the benefit and increase some of the side-effects of ketamine.

You should not drive until the morning after you have had ketamine treatment.

However, when you first start taking ketamine or when your dose is increased you may feel drowsy the next day. You should use common sense and not drive if you feel drowsy. It is your responsibility to decide whether you are fit to drive on each occasion.

Benzodiazepines (such as Diazepam, Lorazepam, Clonazepam and Temazepam), morphine and the epilepsy drug lamotrigine are thought to interact with ketamine so it is advised that these are not taken the night before or the day you have ketamine.

Other than those listed above, ketamine should not affect your other medicines. When you start ketamine you will be asked to complete paperwork asking about your current medications. The ketamine clinic nurse will discuss with you any medications that may interact with ketamine.

Other painkillers including opioids (e.g. codeine), non steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, or paracetamol can be taken at the same time as ketamine.

Before you take or buy any new medicines always tell your doctor or pharmacist that you are having ketamine.

No. There will be a period of 3-4 weeks after your 3 ketamine infusions before starting oral ketamine.  This is to see how you respond to ketamine and how long any benefit lasts.

Not everyone is suitable for oral ketamine treatment, this will be assessed during your telephone follow-up appointment.

No. The person accompanying you will be shown to room where they can have a drink and wait with others.

There are two main reasons for this. Clinic bays are small and staff need room to access the infusion pump during treatment. Also there will be other patients having their treatments at the same time and we try to create a quiet and calm environment.

Additionally, staff are trained and experienced to be able to look after you during your treatment and through any of the side effects associated with ketamine. Friends or family members may find observing this distressing and alarming.

Download information leaflet

PDF file. Requires pdf reader


Your psychiatrist or GP should send a send a referral letter, preferably by email to:

or by post to:

Ketamine Clinic
Warneford Hospital

Version: Web 15 November 2018