Whether drugs expire depends on whether you’re talking about a licensed medicine or an illicit drug. A medicine’s expiry date marks the manufacturer’s guarantee, after which there’s less evidence that it works or whether it’s safe.
Illicit drugs have no expiry dates because they’re unregulated. Some research shows they change as they age, but the bigger risk is that people rarely know what’s in them to begin with.
Whether it’s an old prescription in the cupboard or something you’ve had for a while, understanding what happens as drugs age can help you make safer decisions. It can also help you notice when a question about drugs points to something bigger.
Do drugs expire?
Every licensed medicine has an expiry date. That date is based on stability testing carried out by the manufacturer under controlled conditions. It tells you how long the product will stay at full strength when stored correctly.
Medications and illegal drugs degrade at different rates, but it’s not possible to know how fast or what this means for effects or safety. It’s unlikely that a medication will suddenly become harmful the day after it expires. But the manufacturer can no longer confirm that it works or that it’s safe, so it’s best not to take it.
This is most important for medicines that need an exact dose, or where a weaker or stronger dose could cause a real problem.
Does medicine expire the same way as a use-by date?
The expiry date printed on the packaging is the manufacturer’s date. It applies to the product while it’s unopened and stored correctly.
A use-by date is different. It’s usually shorter and applies once the medicine has been opened or dispensed. Some are printed by the manufacturer, and some are added by the pharmacist. Once a bottle is opened or tablets are taken out of their original packaging, air and moisture can start to affect the medicine.
If your medicine says something like “discard within seven days of opening”, that’s a use-by date. Follow whichever date comes first.
If you’re unsure which applies, your pharmacist can tell you.
How can you tell if medication has expired or is unsafe?
Sometimes you can tell by looking. These are signs that a medicine may no longer be safe.
- A change in colour
- A change in smell
- Tablets crumbling, sticking together, or becoming soft
- Liquid becoming cloudy or containing particles
But a medicine can look and smell fine and still have lost strength, so the date is the most reliable check.
Does cocaine expire? Do MDMA, LSD and other illicit drugs go bad?
Illicit drugs don’t go through the stability testing that licensed medicines do. They’re unregulated, so there’s no quality control and no expiry date, and you can’t know what’s in them to begin with or how they’ve been stored.
Does cocaine go bad?
Cocaine can change in storage, though the research is limited.
A study on the stability of cocaine impurity profiles looked at cocaine stored for 12 months. It found that the cocaine’s mix of trace chemicals changed, especially in low-purity samples kept at 37°C.
Different purity, cutting agents, temperature, and environmental factors like humidity and how cocaine is stored may affect how long the process takes.
Does cannabis go bad?
Cannabis loses strength as it ages. The United Nations Office on Drugs and Crime notes that THC, the main psychoactive compound in cannabis, fell by about 16% after one year, in samples stored at room temperature in the dark.
After two years, the loss was about 26%, and after four years, about 41%.
Does LSD expire?
Research on LSD stability has shown that LSD breaks down when it’s exposed to light or heat. Kept at body temperature or above, it lost 30 to 40% over four weeks, though it was stable at room temperature.
That study tested LSD in urine samples for drug testing, not in the form people take it. How fast LSD degrades in different forms may vary.
Does MDMA expire?
There’s little published research on how MDMA changes in the forms people buy it in. It’s not possible to know whether MDMA in either pills or a powder is safe, has lost strength, or what mix was in there in the first place.
Why expired or unknown substances can be dangerous
With expired medication, the risk is that the drug is no longer doing what it should. It may be weaker, or its chemical makeup may have changed. In some cases, it becomes actively unsafe.
An unknown or illicit substance carries risk before it has had any time to age. The European Commission warns that falsified medicines haven’t been through the checks genuine medicines go through, so they may contain poor-quality or even toxic ingredients.
That warning is about fake pharmaceuticals, but the same is true of any substance you can’t verify.
This includes prescription drugs from outside a pharmacy, such as benzodiazepines purchased online. These are widely prescribed, however dependency on benzodiazepines can also be common.
What happens if you take expired medication?
The US Food and Drug Administration warns that an expired medicine’s chemistry or strength can change, so it may not work as intended. Some expired medicines can also grow bacteria. Weaker antibiotics can fail to clear an infection, and that can lead to antibiotic resistance.
This doesn’t mean every expired tablet is dangerous. But there’s no way to tell from looking at it whether the chemistry has changed. If your medication is past its expiry date, the safest thing to do is not take it.
You can return expired medication to your pharmacy for safe disposal. This is particularly important for opioids and benzodiazepines, because they can be harmful if someone else in your home takes them.
When questions about drug safety point to something more
Usually, a question about whether drugs expire is a practical one, but sometimes it’s connected to something bigger.
You might recognise one or two of these:
- Regularly checking or worrying about what’s in a substance before using it
- Using something despite not knowing what’s in it or how old it is
- The question itself feeling more personal than practical
- Finding that questions about drug safety keep coming up
These don’t necessarily mean there’s a problem, but they could be a reason to begin thinking about your relationship with substances.
Our pages on understanding the risks of drug addiction and how drug use can affect mental health are a good place to carry on reading.
How Castle Health can help with concerns about drug use
If your concern goes beyond a single medicine, Castle Health can help.
We offer both outpatient and residential support for people living with drug use, including prescription drug addiction. There’s no referral needed, and you can talk things through before making any decisions. If your question is about one specific medicine, your pharmacist or GP is usually the best first step.
You can find out more about our approach to drug detox and treatment for drug addiction.
Looking for more information?
We can provide more information and support for anyone looking to understand more about addiction and treatment.
If you’re worried about someone in your life using expired or unknown substances
You might have found medication you didn’t expect, or substances you can’t identify. Or you might have noticed someone using something, and you’re not sure what it is or whether it’s safe.
If you do decide to say something, talk about what you’ve noticed rather than what you think it means. You don’t need to be right about the substance to say you’re worried.
Castle Health can talk you through what you’re seeing and help you decide on a next step. If the person in your life does go on to get treatment, Castle Health’s family support programme offers therapy for families during that process.
If someone becomes unwell after taking something unknown, call 112 or your local emergency services.
Frequently asked questions about whether drugs expire
Is it safe to take medication past its expiry date?
There’s no guarantee. The manufacturer has only tested the product up to that date, so the chemical makeup may have changed in ways you can’t see or smell. The safest approach is to treat the expiry date as a firm line.
Do drugs still work if expired, or do they just become less effective?
Both can happen. Reduced strength is the most common outcome, but sometimes the chemistry changes and makes the drug unsafe. Antibiotics are a particular concern because weaker doses may not fully treat infections.
What types of medication become unsafe (rather than just less effective) after expiring?
The FDA says certain expired medicines can grow bacteria. That can make them unsafe as well as weaker. Antibiotics are another concern, because a weaker dose may not clear an infection and can contribute to antibiotic resistance. If you’re unsure about a specific medicine, your GP or pharmacist can check for you.
Does tramadol degrade or become unsafe after its expiry date?
No confirmed research explains how tramadol specifically degrades. It carries the same general risks as any expired medication. The advice is to get rid of tramadol as soon as it’s expired or no longer needed. Because tramadol is an opioid, it can cause serious harm if someone else in your home takes it, including children. Your pharmacist can advise on how to return it.
