When a drug is laced, it means that it has been mixed with another drug or substance. This is commonly done with cocaine using bulking agents like flour or baking soda to ensure a higher profit margin for the dealers.

Drugs can also be laced with other substances to alter the effects it has on the body.

Recently in the United Kingdom, there has been an ongoing issue with cannabis gummy sweets laced with the spice being sold (1). Cannabis is a natural plant that carries a small risk of overdose, whereas spice – a synthetic version of cannabis, can cause an overdose and even death.

While lacing cannabis with psychoactive and illicit substances is not as common as lacing other, harder drugs, it is not unheard of and remains a very real risk to cannabis users.

It is impossible to tell how much cannabis being sold is laced with other substances because there are no reliable statistics available, however, it is common for drug dealers to lace their product if they have received a low-quality product or simply want to make more money.

Signs of Laced Weed

cannabis plant

Unfortunately, it is incredibly difficult and near-impossible to tell if your weed is laced by using any at-home tests. This is because there are various strains of weed, all of which have varying smells, tastes and colours.

However, if you regularly buy the same strain of weed and you notice it looks or smells different, there is a chance that it has been laced with another substance.

Some users have reported noticing a white powder ‘sprinkled’ on their weed or powder residue left in the baggies their weed comes in. This also would suggest that the weed has been laced.

Why Weed Is Mixed with Other Substances

cannabis oil and plant

As previously stated, dealers often lace their drugs with other substances to make more of a profit or to alter the effects of the drugs. However, lacing marijuana with hard drugs such as heroin is rare because the seller would be losing money by selling a harder drug for a lower price.

It is a concern among some marijuana users that dealers will lace their weed with heroin, meth, or cocaine addiction so that they have a loyal customer and thus make more money, however, this is not believed to be a common occurrence.

That being said, weed can be laced with other substances such as tiny shards of glass to increase the weight of the product.

How to Tell if You Smoked Laced Weed

man holding cannabis spliff

The effects of laced weed will vary depending on what the weed has been laced with. However, if you are a regular weed user and are suddenly experiencing different effects of the same strain of weed you normally use, it is possible that your weed has been laced. 

Weed users commonly report feeling happy and relaxed when they use the drug, however, if you are suddenly feeling energetic and talkative, your weed may be laced with cocaine or meth.

If you hallucinate, your weed may be laced with LSD.

If you feel tired or sick, your weed may be laced with heroin or laundry detergent.

What to Do if You Smoke Laced Weed

weed joint and ashtray

If you regularly smoke weed and feel different from how you usually feel after using, it is possible that your weed was laced and you should seek medical advice.

If you have never smoked weed before and feel sick after your first time, it might be worth getting checked out by a medical professional just to be safe.

If you have smoked weed and are experiencing any symptoms that are in any way concerning, you should seek medical attention.

As previously stated, a marijuana overdose cannot kill you, however, if your marijuana has been laced with something else, an overdose is entirely possible. For this reason, if you believe you have smoked or ingested something unfamiliar to you, you should seek medical advice as soon as possible. 

“Smoking Wet”

Man smoking marijuana

“Smoking wet” is the process of smoking marijuana cigarettes that have been dipped into other substances including embalming fluid, phencyclidine (PCP), or both. 

“Smoking wet” is believed to have originated in the 1970s when marijuana cigarettes were often laced with PCP to give the user an altered experience including hallucinations. During this time, marijuana users referred to PCP as embalming fluid, and somewhere along the line, real embalming fluid ended up being used in the process of creating “wet” cigarettes.

However, inhaling PCP and embalming fluid can lead to organ failure and respiratory failure (2).

Symptoms & Side Effects of Laced Weed

group of people dancing in club

The symptoms and side effects you will experience from smoking laced weed will differ depending on what the weed was laced with and your overall tolerance to substances.

As it is possible to lace weed with a large variety of substances, it is helpful to have an idea of how each substance can affect you when it is smoked in a laced weed cigarette.

Some of the most common substances used to lace weed are:

1. Ketamine

dancers in club

Ketamine is an anaesthetic and is commonly referred to as a ‘horse tranquillizer’. It causes the user to become detached from reality and can produce some visual or auditory hallucinations (3).

The dissociative aspect of ketamine mixed with the psychoactive aspect of marijuana can cause increased hallucinations and feelings of escapism. These effects are what will make users continue to mix these substances, thus creating an addiction.

2. Methamphetamine

Meth crystals

Methamphetamine is a highly addictive stimulant that increases the amount of dopamine released in the brain (4). Short-term effects of methamphetamine are increased alertness, rapid heartbeat and an increase in body temperature.

Methamphetamine is highly addictive and overdosing on this substance can be extremely dangerous.

Because the effects of methamphetamine are usually the opposite of the effects of marijuana, there is no way to tell how meth-laced weed will affect you.

3. Heroin

woman heating drugs on spoon

Heroin is a highly powerful opioid that causes the user to feel an extreme rush of pleasure. However, it is also known to cause mental fog, paranoia and gastrointestinal issues (5)

Smoking weed that has been laced with heroin can be dangerous, especially if the person does not know that it has been laced as this can cause an overdose if they continue to use the drug combination.

The effects of heroin-laced weed can differ from person to person but often include dizziness, lethargy and loss of consciousness.

4. PCP

Phencyclidine (PCP) also known as ‘angel dust’, is a hallucinogenic dissociative substance that is known to make its users feel powerful and invincible.

Mixing PCP with marijuana means that the effects of the substances kick in faster and the high is prolonged.

A marijuana cigarette laced with PCP is said to contain between 1 and 10mg of the substance, while only 0.25mg is needed to produce a sedative effect (6).

Prolonged use of PCP-laced weed can lead to psychosis.

5. LSD


Also known as ‘acid’, LSD is a powerful hallucinogenic substance which can cause users to experience distortions in space and time as well as mood changes.

It is commonly believed that LSD is sensitive to heat and therefore will lose a lot of its potency when the laced cigarette is lit. However, research from 2003 indicates that it is not as sensitive to heat as first thought, and retains its potency for up to 5 minutes even in high temperatures (7).

While an overdose of LSD is not commonly thought to be life-threatening, it can result in a ‘bad trip’ which can be emotionally and psychologically traumatizing.

6. Cocaine

What Makes Cocaine Addictive

Cocaine and marijuana produce different effects. Marijuana causes users to feel relaxed while cocaine is a stimulant and causes alertness and energy.

If someone unknowingly smokes weed that has been laced with cocaine, they may first notice a bitter flavour. However, the after effects can be quite alarming when someone is unaware that their weed has been laced with a stimulant. This can lead to increased paranoia or intense emotional reactions.

7. Embalming fluid

As mentioned above, people used to refer to PCP as embalming fluid, and along the way, real embalming fluid was used to lace weed for a heightened hallucinogenic effect.

Lacing weed with embalming fluid often means the cigarette burns at a slower rate making it last longer and subsequently prolonging the high.

However, embalming fluid is incredibly dangerous and carcinogenic. Smoking weed laced with embalming fluid can cause coordination issues, brain and lung damage, as well as tissue damage in the throat, nose, and esophagus (8).

8. Lead or other heavy metals

cannabis plant

Cannabis plants soak up the lead and heavy metals from the soil and are often used for phytoremediation – which means cannabis plants are used in contaminated soils to make the ground healthy and usable again (9).

Lead and other heavy metals are known to be carcinogenic and there is no way to know how much of these harmful substances have been soaked up into the plant.

9. Fungus and bacteria

As with lead and heavy metals, there is often no way to know whether your weed contains any fungi or bacteria. Sometimes, the weed may appear grey or have some residue on it, however, if you have a pre-rolled weed cigarette, you may not realise your weed is mouldy at all.

Smoking weed that contains bacteria or fungi does not usually produce any life-threatening effects, however, it is likely to make you feel nauseous and can exacerbate other health conditions such as asthma.   

10. Laundry detergent

laundry detergent

Weed is often laced with laundry detergent to make it smell better as well as to increase the weight. It can also enhance the overall appearance making you believe you are getting a higher-quality product.

However, laundry detergent is obviously not for human consumption and smoking weed laced with laundry detergent can make you incredibly sick.

11. Glass

Glass is commonly used to increase the weight of the weed so that dealers make a higher return on their product.

The tiny fragments of glass can cause sores in your mouth and throat, persistent chesty cough and tight chest pains. 

How Common Is Laced Marijuana?

cannabis plant leaves

Marijuana is not known to be commonly sold laced with other substances. This is primarily because other substances are often more expensive than marijuana so it wouldn’t make sense for dealers or suppliers to waste the more expensive drugs in this way.

Weed is most commonly laced by the user to enhance their experience of the drug and to produce heightened effects and prolonged highs.

However, weed being sold already laced with harmful substances is not unheard of and there is often no way to know whether or not your weed is laced with anything until it is too late.

Using glass or laundry detergent is more common because suppliers can make more money this way.

There are some precautions that you can take to try to protect yourself from weed laced with harmful substances, such as:

  • Never buy ground weed
  • If you are familiar with the substance, make sure you inspect it thoroughly before buying it
  • If it smells off, feels gritty, or tastes strange – do not use it.

Get Help for Your Marijuana Addiction

Two people holding hands

You can get help for your cannabis addiction.

Cannabis does not cause physical addiction and therefore does not usually require a long stay in a rehab facility.

Contact one of our addiction specialists today on 0800 326 5559.

We are waiting to take your call and answer any questions you have on addiction and rehabilitation.


[1] BBC News – Experts issue warning over cannabis sweets laced with Spice – https://www.bbc.co.uk/news/newsbeat-60998420

[2] The National Library of Medicine – Smoking Wet – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3568288/

[3] Alcohol and Drug Foundation – Ketamine – https://adf.org.au/drug-facts/ketamine/

[4] National Institute on Drug Abuse – Methamphetamine – https://nida.nih.gov/publications/drugfacts/methamphetamine

[5] National Institute on Drug Abuse – Heroin – https://nida.nih.gov/publications/drugfacts/heroin

[6] National Library of Medicine – Phencyclidine Intoxication and Adverse Effects: A Clinical and Pharmacological Review of an Illicit Drug – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2859735/

[7] The Analysis of Controlled Substances – Chapter 3 LSD – https://doi.org/10.1002/0470868007.ch3

[8] National Drug Intelligence Centre – Fry Fast Facts, Questions and Answers – https://www.justice.gov/archive/ndic/pubs11/12208/index.htm

[9] Penn State Research – Cannabis may contain heavy metals and affect consumer health, study finds – https://www.psu.edu/news/research/story/cannabis-may-contain-heavy-metals-and-affect-consumer-health-study-finds/