Promethazine addiction: The Causes, Symptoms and Side Effects
Promethazine is commonly used to treat allergies, travel sickness and sleep problems, but it’s not as harmless as it may seem. When misused or taken long-term, promethazine can lead to dependence and addiction. In the UK and beyond, growing numbers of people are struggling with promethazine addiction, often unnoticed due to its everyday use and easy availability. Knowing the risks, recognising the signs of promethazine misuse and understanding how treatment can help is essential to staying safe.
What is promethazine?
Promethazine, also called promethazine hydrochloride, is a medicine used in the UK to help with allergies, travel sickness, nausea and sometimes trouble sleeping. You might see it sold under names like Phenergan or Sominex and sometimes as an ingredient in cough and cold medicines.
Promethazine works by calming the signals in your body that make you feel itchy, sick or restless. It is a fairly common medicine that many people pick up from the pharmacy, either with a prescription or, for some brands, over the counter. There are various promethazine side effects, but the most common is drowsiness. This is why many people take promethazine at night like a sleeping pill.
Other promethazine side effects can include a dry mouth, blurred vision and confusion, especially if you take more than the recommended amount.
What is promethazine addiction?
Promethazine addiction means you keep using the medication, even when you know it’s no longer helping or is actively making things in your life worse. As with other types of sleeping pill addiction, it may begin with a prescription, but regular use eventually makes your body expect more and more. This can lead to taking more promethazine than you should or for much longer than it is designed, and this begins the often gradual slide into prescription drug addiction.
But promethazine dependence isn’t always so obvious at first. Many people brush off the early signs, like feeling uneasy when they are running low. But over time, promethazine can become all you think about, and even cutting down a little bit can cause withdrawal. Once you get to this stage, professional sleeping pill addiction treatment can become necessary.
How to spot telltale promethazine addiction symptoms?
Because promethazine isn’t known for causing dramatic “highs” or obvious cravings, it can be tricky to spot when you have crossed the line into addiction. However, these promethazine addiction symptoms may mean you are developing a dangerous reliance:
- Using promethazine for reasons other than why it was prescribed (like to relax or get high)
- Needing larger amounts of promethazine to get the original effects of a smaller dose
- Going to different doctors or chemists to get more promethazine
- Feeling irritable or moody without it
- Avoiding social activities and loved ones so you can use promethazine
- Struggling to concentrate or remember things because of promethazine use
- Feeling physically ill or moody when you try to stop
If any of these sound familiar, it’s a good idea to start looking into promethazine detox and rehab options.
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Start the Promethazine Rehabilitation Process Today
Finding the best addiction treatment is vital for long-term recovery success. Our friendly and compassionate team will hold your hand through the process until you learn to love yourself again.
What factors increase the risk of promethazine addiction?
There are various reasons why some people are more likely to get caught up in promethazine addiction than others. Some of the main causes that go into the mix include:
History of substance use
If you have struggled with addiction before, you may be more naturally at higher risk of getting hooked on promethazine. This is because your brain is already wired to seek relief or escape through substances, which makes promethazine more dangerous.
Taking promethazine recreationally
Young people sometimes abuse “Lean” or “Purple Drank”, nicknames for a drink that is made by mixing cough syrup (often containing promethazine and codeine) with fizzy drinks and sometimes sweets. People use it to try to feel relaxed or get a “high”, but this is very risky and can lead to serious health problems and addiction.
Stressful life circumstances
Struggling with anxiety, depression, or trouble sleeping can push you to use promethazine for relief. It might seem like a simple fix, but self-medicating in this way can quickly spiral out of control.
Easy access and long-term use
When promethazine is easy to get, the temptation to use it more than you should is always there. If you take promethazine for weeks or months at a time, your body and mind are then more likely to become dependent.
Mental health problems
Major stressors like a tough job, grief or relationship problems can make the comfort that promethazine brings feel absolutely necessary. This makes it much easier to slip into regular use and eventual addiction.
Lack of support or awareness
If you don’t have a doctor checking how much you’re using or if you don’t realise how addictive promethazine can be, it is easy for things to get out of hand before you even notice.
Promethazine factsheet
- A study of reports to the European Medicines Agency (EMA) from 2003 to 2019 found 1,543 adverse drug reaction cases concerning promethazine. Out of these, 557 (36%) were linked to misuse, abuse or dependence.
- These included 300 cases of 'drug abuse' (54%) and 117 cases of intentional misuse (21%), many involving other substances like opioids or codeine.
- Among the 557 misuse-related cases, 310 (56%) involved fatal outcomes, often where promethazine was used alongside other sedatives or opioids.
- Broader research on OTC antihistamines and cough medicines (including promethazine) shows they are among the most misused non-prescription drugs globally. Promethazine abuse is most common among young people who often mix it with codeine in “Lean” or “Purple drank”.
What are the dangers of promethazine abuse and addiction?
Promethazine abuse and addiction can cause a huge amount of harm, sometimes before you even notice it’s happening. Some of the biggest dangers of promethazine abuse and addiction include:
Promethazine overdose
Taking too much promethazine can lead to seizures, loss of consciousness, dangerously low blood pressure and even death, especially if you take it with other sedating drugs or alcohol. One of the biggest dangers is that promethazine can slow your breathing, sometimes to the point of stopping completely.
Severe drowsiness and blackouts
Promethazine is known for making people extremely sleepy—even when taken as prescribed. Misusing it can make you so drowsy that you nod off during conversations or fall asleep at dangerous times, like when driving or cooking. In high doses, some people have even blacked out and lost memory of what happened.
Hallucinations and confusion
Promethazine can cause vivid hallucinations or confusion, especially at higher doses or in combination with alcohol or other drugs. Some people have seen or heard things that aren’t there, which can be very frightening and put you in dangerous situations.
Trouble with coordination
Promethazine affects the way your brain controls movement and abusing it can make your arms and legs feel heavy or shaky. This can mean you are more likely to fall over, drop things or get in accidents.
Dangerous heart rhythm changes
At high doses, promethazine can interfere with the way your heart beats. This can cause irregular heart rhythms (arrhythmias), which might make you feel dizzy or faint or, in rare cases, lead to cardiac arrest.
Long-term health issues
Regular abuse of promethazine can affect your liver and kidneys and cause serious harm. Some people also develop or worsen long-lasting mental health issues like anxiety, paranoia or depression, which get worse the longer addiction goes untreated.
Finding help if you have a promethazine addiction
If you’re worried about your use of promethazine or just need someone to talk to, the team at Providence Projects is here for you. We understand how tough it can feel to ask for help, but reaching out is the first step towards feeling better.
Contact us today and our promethazine addiction treatment programme can guide you through every stage of recovery.
Reach out to our expert support team 24 hours a day
Start the Promethazine Rehabilitation Process Today
Finding the best addiction treatment is vital for long-term recovery success. Our friendly and compassionate team will hold your hand through the process until you learn to love yourself again.
Frequently Asked Questions
How long does promethazine stay in your system?
Promethazine usually stays in your body for around two to four days after you take it. Most people feel the effects for about six to twelve hours but traces of the medicine can still be found in your system for a couple of days.
Is promethazine stronger than zopiclone?
Promethazine and zopiclone are different types of medicines so “stronger” depends on what you need them for. Zopiclone is a sleeping pill designed to help you fall asleep quickly and is usually stronger at making you sleep than promethazine. Promethazine can cause drowsiness but it’s mainly used for allergies or travel sickness rather than as a main sleep medicine.
Is it dangerous to combine promethazine with alcohol?
Yes, it can be dangerous to mix promethazine with alcohol. Both can make you very drowsy and slow down your breathing, which could lead to serious problems or even an overdose. It is safest not to drink any alcohol when you’re taking promethazine.
(Click here to see works cited)
- Gabe, Jonathan, et al. “Prescription hypnotics in the news: A study of UK audiences.” Social Science & Medicine, vol. 174, 2017, pp. 43-52. Science Direct, https://www.sciencedirect.com/science/article/pii/S0277953616306487
- Life Lessons. “What is Lean? The Dangers of this Recreational Drug.” Life Lessons, https://lifelessons.co.uk/resource/what-is-lean-the-dangers-of-this-recreational-drug/ – Accessed 29 July 2025.
- NHS. “Promethazine: drowsy (sedating) antihistamine that relieves allergy symptoms.” NHS, https://www.nhs.uk/medicines/promethazine/ – Accessed 29 July 2025.
- Chiappini, Stefania et al. “Beyond the ‘purple drank’: Study of promethazine abuse according to the European Medicines Agency adverse drug reaction reports.” Journal of psychopharmacology (Oxford, England) vol. 35,6 (2021): 681-692. doi:10.1177/0269881120959615