Can You Overdose on Ketamine? Signs, Symptoms & Treatment

Ketamine stands as one of the most commonly utilized anesthetics globally. In medical environments, ketamine is considered highly safe when administered correctly. Overdoses in clinical settings are rare and typically do not lead to lasting adverse effects. However, when used recreationally, ketamine poses significant dangers. Ketamine toxicity can result in serious health complications affecting the cardiovascular, neurological, urogenital, abdominal, and psychiatric systems.

Ketamine is chemically related to the recreational substance phencyclidine (PCP). Although it is roughly one-tenth as potent as PCP, excessive ketamine intake can lead to severe hallucinations, psychosis, and deep sedation, potentially causing respiratory depression, coma, or even fatality. Recreational users often consume ketamine by snorting, injecting into muscles or veins, smoking, or ingesting it orally in pill form or dissolved in liquids.

Symptoms of a Ketamine Overdose

The signs of a ketamine overdose depend largely on the dosage consumed. Lower doses typically induce feelings of euphoria and dissociation, whereas higher doses can cause intense hallucinations, deep sedation, and immobility.

Common symptoms associated with a ketamine overdose include:

• Respiratory Depression: Characterized by slow or irregular breathing.
• Psychosis: Severe mental disturbances.
• Nausea and Vomiting: Gastrointestinal distress.
• Lethargy: Extreme tiredness or lack of energy.
• Excessive Salivation: Increased production of saliva.
• Trismus (Lockjaw): Involuntary tightening of the jaw muscles.
• Reduced Pain Sensation: Diminished ability to feel pain.
• Nystagmus: Involuntary eye movements, which can be lateral, horizontal, or rotary.
• Confusion: Difficulty in thinking clearly.
• Slurred Speech: Impaired ability to speak coherently.
• Muscle Rigidity: Stiffness in the muscles.
• Profound Sedation: Deep levels of unconsciousness.
• Hallucinations: Seeing or hearing things that aren’t present.
• Unconsciousness: Lack of awareness and responsiveness.
• Seizures: Sudden, uncontrolled electrical disturbances in the brain.
• Coma and Death: In extreme cases, overdose can lead to coma or be fatal.

One of the most perilous symptoms of a ketamine overdose is respiratory depression. This condition occurs when ketamine suppresses the brain’s control over breathing, leading to dangerously slow and irregular breaths. Respiratory depression can result in unconsciousness, coma, irreversible brain damage, or death if not promptly treated. A ketamine overdose is a medical emergency requiring immediate intervention to prevent fatal outcomes.

What Are the Causes of Ketamine Overdose?

Recreational Use

In recent years, ketamine has gained popularity as a “club drug.” The primary cause of ketamine overdose is recreational misuse, where individuals consume large doses to achieve euphoric highs and altered states of consciousness. Disturbingly, ketamine has also been used as a date rape drug due to its anesthetic, amnesic, and dissociative effects.

Polysubstance Abuse

Physiologically, ketamine disrupts multiple signaling pathways in the brain responsible for maintaining homeostasis, including regulation of breathing, heart rate, metabolism, and cognitive functions. While fatal overdoses from ketamine alone are rare, the risk significantly increases when ketamine is combined with other substances, particularly alcohol.

Lethal Dosage

Determining a specific lethal dose of ketamine in humans is challenging due to various influencing factors such as body weight, metabolic rate, overall health, genetic makeup, prior ketamine exposure, and concurrent use of other drugs or alcohol. A general estimate for a lethal dose is around 600 mg/kg, which equates to approximately 4.2 grams for a 155-pound individual.

For comparison, standard anesthetic doses in medical settings are usually well below 10 mg. It’s crucial to recognize that this estimate pertains to ketamine use without other substances; combining ketamine with alcohol or other drugs greatly heightens the risk of overdose.

Ketamine Drug Interactions

Ketamine interacts with numerous bodily functions, often producing conflicting effects. For instance, while high doses of ketamine can cause respiratory and cardiac depression, it also stimulates the sympathetic nervous system, leading to increased heart and breathing rates. These opposing actions may somewhat mitigate the lethality of ketamine overdoses when used alone.

However, mixing ketamine with other drugs, especially those that depress the central nervous system (CNS), significantly elevates the risk of a ketamine-related overdose. When CNS depressants are combined with ketamine, their effects on the CNS can become synergistic, meaning the combined impact is greater than the sum of their individual effects. This synergy can lead to potentially life-threatening respiratory depression.

Common CNS depressants that are often abused alongside ketamine include:

• Alcohol
• Prescription Opioids
• Benzodiazepines
• Heroin

Additionally, CNS stimulants such as cocaine, ecstasy, and methamphetamine are sometimes used with ketamine. Although the dangers of combining ketamine with stimulants are less well-documented, animal studies indicate that the lethality of such combinations is significantly higher compared to using either substance alone.

Ketamine Overdose Fatalities

Deaths solely attributed to ketamine without the involvement of other drugs are uncommon. The primary risk of fatality arises when ketamine is abused in conjunction with other substances, particularly alcohol and other drugs of abuse.

Treatment for Ketamine Overdose

Most ketamine overdoses can be managed with supportive care. The duration and severity of overdose symptoms depend on the amount and method of ketamine intake, with acute effects lasting from 15 minutes to several hours. Typically, individuals suspected of a ketamine overdose should be monitored by healthcare professionals for at least six hours to manage any potential complications effectively.

In cases where large doses of ketamine are consumed alongside other substances, activated charcoal may be administered to reduce absorption. However, there are no FDA-approved medications specifically designed to treat a ketamine overdose.

Benzodiazepine-Assisted Treatment

For individuals experiencing agitation or psychosis due to ketamine overdose, benzodiazepines such as lorazepam or diazepam may be used to alleviate immediate symptoms. These medications can also help control psychomimetic effects (like delusions or delirium), high blood pressure, elevated body temperature, and seizures caused by high doses of ketamine.

It is essential that benzodiazepines are only administered by medical professionals in a clinical setting, as they are CNS depressants and can exacerbate ketamine-induced respiratory depression and increase the risk of fatality.

Preventing Ketamine Overdose

The most effective strategy to prevent a ketamine overdose is to avoid misuse or abuse of the drug altogether. Occasional, low doses of ketamine are generally well-tolerated and carry minimal risk when not combined with other substances. However, even infrequent use of low doses can lead to long-term physical and mental health issues. The risk of overdose significantly rises when ketamine is taken with other drugs.

If you or someone you know is struggling with ketamine use disorder, The Recovery Village Indianapolis is here to help. Our dedicated team understands the complexities of addiction and is committed to guiding you toward recovery. Contact us today to explore our comprehensive rehabilitation programs and take the first step towards a healthier, sober life.