Mixing Sprite with prescription cough syrup containing codeine and promethazine creates a drink commonly called “lean” or “purple drank.” It produces a slow, sedative high that depresses the central nervous system, slowing breathing and heart rate while inducing euphoria and extreme drowsiness. The combination is significantly more dangerous than either ingredient alone because the two active drugs amplify each other’s effects on the brain.
What the Mixture Contains
The cough syrup used in lean is not an over-the-counter product. It’s a prescription formulation that combines two drugs: codeine, an opioid painkiller, and promethazine, an antihistamine with strong sedative properties. Sprite or another lemon-lime soda serves as the mixer to mask the syrup’s bitter medicinal taste. Hard candies like Jolly Ranchers are often dissolved in the cup for additional sweetness and color.
The DEA classifies cough preparations containing codeine as Schedule V controlled substances when the codeine concentration stays below 200 milligrams per 100 milliliters. Products with higher codeine content per dose fall under Schedule III. Both categories require a prescription, and obtaining or distributing the syrup outside a prescription is a federal offense.
How It Affects the Brain and Body
Codeine and promethazine each depress the central nervous system through different pathways, and combining them creates a compounding effect that neither drug produces on its own. Codeine binds to opioid receptors in the brain, producing pain relief, euphoria, and slowed breathing. Promethazine blocks histamine receptors and dopamine activity, which induces deep drowsiness and a quiet, sedated state.
The critical issue is that promethazine potentiates the opioid. It intensifies and prolongs the high from codeine in a way that opioid users describe as qualitatively different from taking an opioid alone. This was actually recognized medically as far back as the 1950s, when doctors used the combination to achieve sedation with lower opioid doses. In the context of recreational use, though, people are not taking lower doses. They’re drinking large, uncontrolled amounts, and the potentiation effect pushes the combined sedation into dangerous territory. Prescription guidelines recommend cutting the opioid dose by 25 to 50 percent when promethazine is also being used, which gives a sense of how much stronger the mixture becomes.
Short-Term Effects
The immediate experience of lean typically includes:
- Intense drowsiness and a feeling of heavy relaxation, often described as a “slowed down” sensation
- Euphoria from opioid receptor stimulation
- Impaired coordination and cognition, making basic tasks like driving extremely dangerous
- Constricted pupils, one of the hallmark signs of opioid activity
- Nausea and constipation, common side effects of any opioid
At higher amounts, the effects can escalate to hallucinations, confusion, and significant respiratory depression, where breathing becomes dangerously slow and shallow. Some users experience a breathing rate as low as 4 to 6 breaths per minute, compared to the normal 12 to 20. This is the mechanism that kills people: the brain’s drive to breathe is suppressed to the point where the body simply stops getting enough oxygen.
Why the Combination Is Especially Dangerous
Each drug in the mixture independently slows breathing. Together, they create a compounding respiratory risk that makes overdose far more likely than with codeine alone. Research on the combination identifies several life-threatening outcomes from consuming large quantities: delirium, severe respiratory depression, overdose, a dangerous heart rhythm change called QT prolongation, and neuroleptic malignant syndrome, a rare but potentially fatal reaction involving high fever and muscle rigidity.
Adding alcohol, benzodiazepines, or any other sedating substance on top of lean dramatically increases the danger. Promethazine already intensifies the sedative action of opioids, narcotics, alcohol, and tranquilizers. Stacking another depressant onto that combination can push someone from heavily sedated to not breathing in a very short window.
The soda itself contributes a separate health problem. A single serving of lean can contain an enormous amount of sugar from both the syrup and the Sprite. Chronic use bathes the teeth in a highly acidogenic and cariogenic mixture, meaning it both erodes enamel through acidity and feeds the bacteria that cause cavities. Heavy soda consumption is already linked to severe tooth decay and dental erosion, and sipping a sugary drink slowly over hours, which is how lean is typically consumed, maximizes that damage.
Dependence and Tolerance
Codeine is an opioid, and regular use produces physical dependence the same way stronger opioids do. The body adapts to the drug’s presence, requiring increasing amounts to achieve the same high. This tolerance cycle is particularly treacherous with lean because the drink format makes it easy to lose track of dosing. There’s no pill count to monitor. A person just keeps sipping.
Withdrawal from codeine dependence involves the same general pattern as other opioid withdrawals: muscle aches, sweating, anxiety, insomnia, nausea, vomiting, and diarrhea. Symptoms typically begin within hours of the last dose and can persist for days to over a week depending on how heavy and prolonged the use was. The psychological dependence can be even harder to shake, particularly since lean use is deeply embedded in certain music and social scenes that reinforce continued use.
Signs of Overdose
The classic signs of an opioid overdose form a recognizable triad: pinpoint pupils, slowed or stopped breathing, and decreased consciousness. A person experiencing a lean overdose may have extremely shallow breathing, blue-tinged lips or fingertips from lack of oxygen, produce frothy sputum, or become completely unresponsive. Wheezing can occur because opioids also constrict the airways.
If someone shows these signs, the priority is getting them breathing. Naloxone, the opioid reversal drug available as a nasal spray in many pharmacies, can rapidly restore normal breathing when administered in time. The goal is to reverse the respiratory depression, not necessarily wake the person up completely. Because promethazine’s sedative effects are not reversed by naloxone, the person may remain drowsy even after treatment, and their breathing needs to be monitored closely until emergency help arrives.