The term “getting crossed,” or “crossfading,” describes consuming two or more psychoactive substances simultaneously, such that their effects overlap. This polysubstance use most commonly involves combining alcohol and cannabis, though it applies to any mixture of drugs. Combining substances creates an interaction that is more hazardous and unpredictable than using either drug alone. The danger stems from the body and brain being subjected to multiple chemical changes at once, often leading to effects that exceed user expectations. This article explores the pharmacological mechanisms, acute physical and psychological symptoms, and long-term health consequences associated with this practice.
Understanding Synergistic Drug Interactions
The danger of mixing substances is rooted in synergism, a pharmacological principle where the combined effect of two substances is significantly greater than the sum of their individual effects—often described as a one-plus-one-equals-three outcome. This involves the substances interfering with multiple neurochemical pathways in the Central Nervous System (CNS) simultaneously.
When two substances from the same class are combined, such as two CNS depressants like alcohol and benzodiazepines or opioids, the risk is multiplied. Both compounds slow down brain activity, suppressing functions like heart rate and respiration. The synergistic suppression of the respiratory drive can quickly lead to respiratory depression and failure, a leading cause of fatal overdose.
Conversely, combining drugs from opposing classes, such as a depressant (alcohol) and a stimulant (cocaine), presents an equally severe risk. The stimulant temporarily masks the sedating effects of the depressant, causing the user to mistakenly believe they are less intoxicated. This masking effect can lead to the consumption of dangerously high doses of the depressant, resulting in acute poisoning or overdose once the stimulant wears off.
Immediate Physical and Psychological Risks
The immediate consequences of getting crossed result directly from unpredictable synergistic interactions. For example, combining alcohol and cannabis allows alcohol to increase the absorption of tetrahydrocannabinol (THC) into the bloodstream. This physiological change intensifies the effects of cannabis and elevates the risk of negative side effects.
A common acute physical outcome is severe impairment of motor control and coordination, leading to poor judgment and an increased risk of accidents or injury. The combined effect on the CNS can also lead to disorienting experiences like “the spins” or sudden blackouts, where memory formation is temporarily halted.
Acute psychological distress is a frequent risk, often manifesting as extreme anxiety, panic attacks, or intense paranoia. This cluster of symptoms, sometimes called “greening out,” also includes severe physical discomfort such as dizziness, profuse sweating, nausea, and uncontrollable vomiting. For those with pre-existing mental health vulnerabilities, the chemical assault can trigger or exacerbate underlying anxiety or mood disorders.
The greatest immediate physical risk is acute poisoning and overdose. When two depressants are mixed, the risk of life-threatening respiratory failure is amplified due to the compounded suppression of the brainstem’s control over breathing. Even combinations that do not suppress breathing can lead to acute medical emergencies, as impaired judgment and loss of consciousness increase the likelihood of accidental trauma or aspiration.
Increased Risk of Dependence and Chronic Health Effects
Beyond the immediate dangers, polysubstance use accelerates the development of long-term health problems. Regularly mixing substances increases the speed at which tolerance develops, requiring higher and more frequent doses to achieve the desired effect. This pattern of escalating use enhances the risk of developing a substance use disorder, characterized by dependence and addiction to multiple compounds.
Chronic polysubstance use places immense strain on major bodily organs responsible for processing toxins. The liver and heart are particularly vulnerable, with prolonged mixing increasing the risk of serious conditions like liver damage, cardiovascular disease, and irregular heartbeats. Combining substances complicates the body’s detoxification processes, as each introduces its own toxic burden.
Mental health consequences are also more pronounced and sustained in polysubstance users. The continuous disruption of multiple neurotransmitter systems can exacerbate or precipitate chronic mental health conditions, including severe anxiety, depression, and psychotic disorders. Polysubstance users often report poorer physical and mental health status compared to single-substance users, highlighting the lasting negative impact on overall well-being.