Can You Take Antidepressants During Ketamine Therapy?

Patients rarely arrive for ketamine therapy without a medication history.

Many have spent years trying SSRIs, SNRIs, mood stabilizers, sleep medications, anti-anxiety drugs, or combinations of several prescriptions. Some medications helped for a while. Others caused side effects. Some never worked.

A common question is:

Do I need to stop my antidepressant before starting ketamine?

In many cases, the answer is no. Patients may continue an existing antidepressant while receiving ketamine treatment.

But that does not mean every medication should be treated the same way.

The safest approach is a complete medication review with the clinician providing ketamine therapy and, when applicable, the clinician who prescribed the existing medications.

Do Not Stop Psychiatric Medication on Your Own

This is the most important point.

Do not abruptly stop an antidepressant, benzodiazepine, mood stabilizer, or other psychiatric medication because you are preparing for ketamine treatment.

Suddenly discontinuing medication can cause:

• Withdrawal symptoms

• Rebound anxiety

• Sleep disruption

• Mood deterioration

• Flu-like symptoms

• Dizziness

• Irritability

• Return of the condition being treated

Medication changes should be deliberate and medically supervised.

Ketamine and SSRIs

SSRIs include medications such as sertraline, escitalopram, fluoxetine, paroxetine, and citalopram.

Many patients receiving ketamine for depression continue taking an SSRI. These medications work through different primary pathways: SSRIs primarily affect serotonin signaling, while ketamine’s antidepressant effects are associated more closely with glutamate and NMDA-receptor activity.

The fact that the mechanisms differ is one reason ketamine can be considered when serotonin-focused treatments have not produced enough relief.

However, the clinical team still needs to know:

• The exact medication

• The daily dose

• How long it has been taken

• Whether the dose recently changed

• Any side effects

• Whether other serotonergic medications are involved

Ketamine and SNRIs

SNRIs include venlafaxine, desvenlafaxine, and duloxetine.

These medications affect serotonin and norepinephrine. They may also influence blood pressure in some patients, which is relevant because ketamine and esketamine can temporarily increase blood pressure.

This does not automatically prevent treatment. It means blood-pressure history and monitoring matter.

What About Benzodiazepines?

Benzodiazepines include medications such as alprazolam, lorazepam, clonazepam, and diazepam.

They may be prescribed for anxiety, panic symptoms, muscle tension, or sleep. The relationship between benzodiazepines and ketamine deserves special attention because some research suggests that higher or concurrent benzodiazepine exposure may reduce or delay ketamine’s antidepressant response.

The available evidence is not conclusive, and studies have been limited. Still, this potential interaction is important enough for the treating clinician to consider. (PubMed)

Patients should not skip or reduce benzodiazepines without medical direction. Abrupt withdrawal can be dangerous.

Instead, the clinician may consider factors such as:

• Dose

• Timing

• Frequency

• Duration of use

• Reason for prescription

• Withdrawal risk

• Whether an adjustment is clinically appropriate

Ketamine and Mood Stabilizers

Some patients receiving ketamine have bipolar depression or take mood stabilizers because of a prior manic or hypomanic episode.

Common medications include lithium, lamotrigine, valproate, and certain atypical antipsychotics.

Research on how these medications interact with ketamine is mixed and still developing. A review found no clear significant interaction with lithium, while evidence concerning lamotrigine has been inconsistent. More recent real-world evidence has not found a clear reduction in ketamine or esketamine outcomes associated with lamotrigine. (PubMed)

This is exactly why online medication lists cannot substitute for individualized review.

Ketamine and Stimulant Medications

Stimulants may be prescribed for ADHD, narcolepsy, or other conditions.

Because stimulants can raise heart rate or blood pressure, their use may affect how the treatment team plans and monitors ketamine or Spravato sessions.

The FDA prescribing information for Spravato specifically notes that psychostimulants may increase blood pressure, reinforcing the need for monitoring. (FDA Access Data)

A clinician may give instructions about timing on treatment days, but patients should not assume that they must stop the medication.

Ketamine and Sleep Medications

Sleep medications vary widely.

Some are sedating antidepressants. Others are benzodiazepines, antihistamines, non-benzodiazepine hypnotics, antipsychotics, or supplements.

Since ketamine and Spravato can cause sedation and temporary cognitive or perceptual effects, the treatment team needs a complete list — including medications patients consider routine or harmless.

This includes:

• Prescription sleep aids

• Over-the-counter antihistamines

• Melatonin

• Cannabis products

• Alcohol use

• Herbal supplements

Why the Full Medication List Matters

Drug interactions are only part of the reason.

Medication history also helps the clinician understand:

• What has already been tried

• Whether the diagnosis needs reassessment

• Whether symptoms may be medication-related

• Whether withdrawal is contributing to mood changes

• Whether blood-pressure risk is elevated

• Whether sedation could be intensified

• Whether bipolar-spectrum symptoms are present

Bring a current list to the consultation rather than relying on memory.

Include the medication name, dose, prescribing clinician, timing, and reason for use.

What About Spravato and Oral Antidepressants?

Current FDA labeling allows Spravato for adult treatment-resistant depression either as monotherapy or together with an oral antidepressant. For depressive symptoms associated with major depressive disorder and acute suicidal ideation or behavior, it is indicated in conjunction with an oral antidepressant. (JNJ Labels)

That distinction matters because the appropriate medication plan depends partly on the condition being treated.

Questions to Ask the Clinician

Before beginning ketamine or Spravato, ask:

• Should I take my normal medications on treatment day?

• Should any medication timing change?

• Could a benzodiazepine affect my response?

• Are my blood-pressure medications adequate?

• Could my stimulant increase treatment-day risk?

• Should my psychiatrist be involved in planning?

• What symptoms should I report before the session?

• Could any supplements or cannabis products interact with treatment?

The Bottom Line

Many patients continue antidepressants during ketamine therapy. The presence of an SSRI, SNRI, mood stabilizer, or another psychiatric medication does not automatically disqualify someone from treatment.

But every medication — including benzodiazepines, stimulants, sleep aids, supplements, and cannabis — should be disclosed.

The safest plan is never “stop everything.”

It is a coordinated plan based on diagnosis, medical history, current prescriptions, and the specific treatment being considered.