Ketamine Troches and Pregnancy: What You Need to Know

The Clear Recommendation

Ketamine troches should not be used during pregnancy or while breastfeeding unless a medical provider has made a specific, individualized determination that the benefits clearly outweigh the risks. This is the consensus position across major medical guidelines and aligns with the general contraindications for ketamine treatment.

This article explains the reasoning behind this recommendation, what the evidence shows, and how to approach treatment planning if pregnancy is a consideration.

Ketamine and Pregnancy: What the Evidence Shows

Animal Studies

The most concerning data comes from animal research:

• Neurodevelopmental toxicity: Studies in rodents and non-human primates have demonstrated that exposure to NMDA receptor antagonists (including ketamine) during critical periods of brain development can cause widespread neuronal apoptosis — programmed cell death in developing brain cells. This effect has been observed at anesthetic doses administered for prolonged periods.
• The vulnerable window: In animal models, the period of greatest vulnerability corresponds to the third trimester of human pregnancy and the first few years of postnatal life, when synaptogenesis (formation of connections between brain cells) is most active.
• Dose and duration matter: The neurotoxic effects in animal studies were most pronounced with prolonged or repeated high-dose exposure. Single brief exposures at sub-anesthetic doses have shown less consistent effects, but the data is insufficient to establish a safe threshold.

The FDA issued a Drug Safety Communication in 2016 noting that prolonged or repeated use of general anesthetic and sedation drugs (including ketamine) during the third trimester of pregnancy may affect brain development. While this was primarily directed at surgical anesthesia, the warning encompasses ketamine in all formulations.

Human Data

Human evidence on ketamine exposure during pregnancy is extremely limited:

• No randomized controlled trials have evaluated ketamine safety during human pregnancy — and for ethical reasons, none are expected
• Case reports and retrospective data from emergency use of ketamine in pregnant women (e.g., for anesthesia during emergency procedures) have not demonstrated a clear pattern of birth defects, but these represent brief, single exposures — very different from repeated troche use over weeks or months
• Epidemiological data is insufficient to quantify the risk of sublingual ketamine use during pregnancy
• Recreational ketamine use during pregnancy has been associated with adverse outcomes in case reports, including low birth weight and neonatal complications, but recreational use involves uncontrolled doses, frequency, and co-substance exposure, making it difficult to isolate ketamine's specific effects

The Precautionary Position

Given the animal evidence of neurodevelopmental toxicity, the absence of reassuring human data, and the availability of alternative treatments for most conditions that troches address, the medical consensus is that ketamine should be avoided during pregnancy unless no reasonable alternative exists.

Specific Risks by Trimester

First Trimester

The first trimester is the period of organogenesis — when the fetus's major organs form. While ketamine has not been definitively linked to structural birth defects (teratogenicity) in humans, the lack of data means risk cannot be excluded. Many medications are avoided during this period as a precaution.

Second Trimester

Less is known about risks during the second trimester specifically. The brain is developing rapidly, and NMDA receptors play a role in normal neurodevelopment. Blocking these receptors during this period has theoretical risks based on the pharmacological mechanism.

Third Trimester

The third trimester is the period of greatest concern based on animal data. Synaptogenesis is at its peak, and this is when animal studies have demonstrated the most significant neuronal apoptosis from NMDA receptor antagonists. Repeated ketamine exposure during this period carries the highest theoretical risk to fetal brain development.

Ketamine and Breastfeeding

Transfer into Breast Milk

Ketamine is a lipophilic (fat-soluble) drug with a relatively low molecular weight — properties that facilitate transfer into breast milk. Limited data suggests:

• Ketamine does appear in breast milk following maternal administration
• The metabolite norketamine also transfers into breast milk
• The exact concentration in milk relative to maternal blood levels has not been well-characterized for sublingual dosing

Infant Exposure Concerns

A nursing infant exposed to ketamine through breast milk would be at risk for:

• Sedation: Ketamine's sedative and dissociative effects could affect an infant's alertness and feeding behavior
• Neurodevelopmental effects: The same concerns about NMDA receptor blockade during brain development that apply during pregnancy continue to apply during the rapid postnatal brain growth period of infancy
• Accumulation: Infants have immature liver and kidney function, meaning they metabolize and excrete drugs more slowly than adults. Even small amounts of ketamine in breast milk could accumulate with repeated exposure.

Practical Guidance for Nursing Mothers

If you and your provider determine that ketamine treatment is medically necessary while breastfeeding (an uncommon decision reserved for severe, refractory conditions), potential risk reduction strategies include:

• Pump and dump: Expressing and discarding breast milk for a defined period after each troche session. The appropriate duration depends on ketamine's elimination half-life (approximately 2.5 to 3 hours for ketamine, longer for norketamine). A conservative approach would discard milk for 12 to 24 hours after a session.
• Supplemental feeding: Using formula or previously stored breast milk for feedings during the elimination period
• Reduced session frequency: Minimizing the number of weekly sessions to reduce cumulative infant exposure

These are harm-reduction strategies, not guarantees of safety. The decision should be made collaboratively with your prescriber and your infant's pediatrician.

Planning Treatment Around Pregnancy

If You Are Currently Using Troches and Considering Pregnancy

Discuss your plans with your prescriber before becoming pregnant. A thoughtful approach includes:

1. Taper and discontinue troches before attempting conception. Work with your provider on a safe tapering plan that accounts for your mental health stability.
2. Establish alternative treatment before stopping ketamine. For depression and anxiety, this may include optimizing traditional medications that have established safety profiles during pregnancy (certain SSRIs, for example), psychotherapy, or other evidence-based interventions.
3. Plan for postpartum resumption if appropriate. Many patients can resume troche treatment after delivery and after breastfeeding is complete (or earlier if they choose not to breastfeed).

If You Discover You Are Pregnant While Using Troches

• Stop taking troches and contact your prescriber immediately
• Do not panic. Brief, low-dose exposure in early pregnancy (before the period of maximum vulnerability) does not automatically mean harm has occurred. The animal data that drives concern involves prolonged, high-dose exposure.
• Inform your obstetrician about your ketamine use, including the dose, frequency, and duration
• Work with both your prescriber and OB to develop a treatment plan for the remainder of the pregnancy

If You Have Severe, Treatment-Resistant Depression During Pregnancy

This is the most difficult clinical scenario. Untreated severe depression during pregnancy also carries significant risks — to both the mother and the developing fetus — including preterm birth, low birth weight, preeclampsia, impaired bonding, and maternal self-harm. In extremely rare cases, a provider may determine that the risks of untreated maternal illness outweigh the potential risks of ketamine.

This decision is highly individualized and should involve:

• A psychiatrist experienced in perinatal mental health
• The patient's obstetrician
• Thorough informed consent about the limited data and potential risks
• Exhaustion of safer alternatives first

Fertility Considerations

Current evidence does not suggest that ketamine at therapeutic doses causes infertility in women or men. However, the effects of chronic sublingual ketamine use on reproductive hormones, ovulation, or sperm quality have not been systematically studied. If you have fertility concerns, discuss them with your provider.

What About Partners?

There is no established evidence that a male partner's use of ketamine troches at therapeutic doses affects sperm quality, conception outcomes, or fetal health. The concerns discussed in this article pertain to direct fetal exposure through the pregnant person's bloodstream or through breast milk.

Key Takeaways

• Ketamine troches are contraindicated during pregnancy and breastfeeding in the vast majority of situations
• Animal studies show potential neurodevelopmental harm, particularly during the period equivalent to the human third trimester
• Human data is too limited to quantify the risk, which is itself a reason for caution
• Plan ahead: discontinue troches before conception and establish alternative treatment
• If you discover you are pregnant while on troches, stop and contact your providers — brief early exposure is not the same as prolonged third-trimester exposure
• The decision to use ketamine during pregnancy or nursing is reserved for extraordinary circumstances and requires careful specialist consultation

References

• FDA Drug Safety Communication: FDA Review Results in New Warnings About Using General Anesthetics and Sedation Drugs in Young Children and Pregnant Women (2016) — FDA warning on anesthetic agents during pregnancy
• Brambrink AM, et al. Ketamine-Induced Neuroapoptosis in the Fetal and Neonatal Rhesus Macaque Brain. Anesthesiology, 2012 — Primate study on ketamine neurodevelopmental toxicity
• American College of Obstetricians and Gynecologists: Depression During Pregnancy — ACOG guidance on managing psychiatric illness during pregnancy
• NIH LactMed Database — Reference database on drugs and lactation
• WHO: Ketamine Pharmacology and Toxicology — Comprehensive pharmacological review including reproductive toxicity data