What is Methaqualone (Quaaludes)?

Methaqualone (commonly known by the brand names Quaalude in the US and Mandrax in the UK) is a synthetic anxiolytic (anxiety reducing) sedative hypnotic drug which has effects similar to those of barbiturates. It was initially synthesised in 1951 and introduced clinically as a ‘safe’ barbiturate substitute to induce sleep. Methaqualone then became popular recreationally in the 1960s. The drug is now listed in Class B, making its production and distribution illegal.

What does Methaqualone look like and what are the different types?

Methaqualone exists as a white crystalline powder. Clinically, it was available in tablet or capsule form for oral consumption.


Illicitly produced methaqualone is commonly a more grey or brown powder.

How is Methaqualone used?

Methaqualone was originally prescribed to treat insomnia. It is a sedative drug which causes relaxation and sleepiness. The drug later became popular recreationally and was commonly used in disco clubs, hence the nickname of “disco biscuits”. Methaqualone was popular recreationally due to the euphoric “high” it produces.


Tablets are usually 250-300mg per tablet and water-soluble capsules are consumed orally. When using the drug illicitly, some people may also crush up tablets and smoke the powder. Some users liquefy the drug and inject the solution intravenously. IV injection comes with the risk of infection if needles are shared.

How does Methaqualone work as a drug in the body and brain?

Methaqualone molecules bind to GABA receptors, the inhibitory neurotransmitter. Increasing activity of GABA slows down the brain and reduces neuronal activity. Increased activity of GABA causes a reduction of blood pressure and heart rate, along with reduced breathing rate, overall leading to a state of relaxation. 

What are the effects of Methaqualone?

The effects of methaqualone can typically be felt around 30 minutes after the drug is taken and last for 5-8 hours.


These effects include:


  • Relaxation
  • Sleepiness
  • Euphoria
  • Reduced blood pressure
  • Nausea and vomiting
  • Dizziness
  • Fatigue
  • Sweating
  • Tingling sensation in arms and legs
  • Seizures
Does Methaqualone have any medical uses?

Methaqualone is no longer used in a medical context due to concerns over the drug’s potential for harm. When first produced, it was used to treat insomnia. Methaqualone is now a class B drug in the UK, making its production and distribution illegal.

What are the risks of using Methaqualone? Can they be avoided or reduced?


Taking an overdose of methaqualone can lead to seizures, comas, and fatality. The range of dangerous doses varies from person to person and depends on factors such as tolerance. Taking methaqualone alongside other drugs increases the risk of overdose, particularly other depressant drugs such as alcohol.


If a person has taken an overdose, heavier sedation than desired may occur, they may have difficulty concentrating, make irrational decisions and speak slowly or slur their words along with displaying a lack of coordination. The person’s breathing may become shallow, and their blood pressure may drop. If an overdose is suspected, medical help must be sought immediately.


To reduce the risk of overdose, users should start with a small dose and see how they feel rather than taking a larger dose all at once. Having a trusted person present when using methaqualone is advisable, as they can help in the event of an overdose.



Tolerance to methaqualone builds up rapidly, causing users to take higher and higher doses to produce the same effects. Methaqualone is both physically and psychologically addictive. Addiction increases the risk of overdose and can lead to users experiencing withdrawal symptoms if they suddenly stop using the drug.


These symptoms include:

  • Restlessness
  • Insomnia
  • Confusion
  • Headaches
  • Irritability
  • Hallucinations
  • Muscle tremors
  • Seizures

If you are using methaqualone, it is important to be aware of the signs of addiction. For example, you may become angry or irritable when you run out of the drug, you may lose interest in your hobbies and your methaqualone use may be putting strain on your personal relationships. Medical help is available to those who are experiencing addiction.



Illicitly produced methaqualone may actually contain none at all. Instead, it may be mix of different barbiturates and benzodiazepines, for example. Taking illicitly produced methaqualone may lead to users taking a drug they didn’t intend to. This in turn can lead to overdose of a different drug, as the dosages may not be the same.

Are there health conditions that make Methaqualone more dangerous?

As use of methaqualone lowers blood pressure, it may be more dangerous for those with existing heart conditions to take the drug. The risk of seizures is also linked to its use, therefore, those who suffer from seizures should avoid use.

Can Methaqualone be used with other drugs?

Methaqualone should never be used alongside other drugs. Mixing any drugs increases the risks of both substances.


Mixing with alcohol and other depressant drugs is particularly dangerous and should be avoided. Overdose may occur at a lower dosage of methaqualone when mixed with alcohol.

How addictive is Methaqualone?

Methaqualone is highly addictive. The drug produces a pleasurable experience for users, leading people to want to take more. Physical and psychological tolerance develops quickly, leading users to take continually bigger doses to experience the same effects. This increases the risk of overdose and over time, the drug may be used more to cope with the unpleasant withdrawal symptoms rather than for pleasure.

What are the harms of Methaqualone addiction and withdrawal?

If a person is addicted to methaqualone, the risk of them overdosing increases as they will need to take an ever-increasing dose to achieve the same effects.


The symptoms of withdrawal include:


  • Restlessness
  • Insomnia
  • Confusion
  • Headaches
  • Irritability
  • Hallucinations
  • Muscle tremors
  • Seizures


As with addiction to any drug, addiction to methaqualone can also cause problems at work and school, put a strain on relationships with family and friends and cause physical and mental health issues.


What are the long-term effects of methaqualone on health and wellbeing?


Long term use of methaqualone can lead to various physical and psychological effects.


Physical effects include:

  • Cardiovascular disfunction
  • Motor disfunction
  • Respiratory depression
  • Extreme sensitivity to light
  • Numbness of fingers and toes


Psychological effects include:

  • Delirium
  • Insomnia
  • Anxiety
  • Depression


Harm reduction advice for Methaqualone users

How much are you taking and how often?

Methaqualone addiction and withdrawal can cause considerable harm to quality of life and health. If you begin to develop tolerance to the effects of methaqualone, this should be taken as a warning sign that the drug may be harmfully affecting your body.


Are you mixing methaqualone with any other drug?

Mixing drugs can cause unpredictable effects and increase the risk of overdose and undesired effects of both drugs.


How are you taking it?

Some routes of administration carry more risk than others, such as intravenous injection. If you are injecting methaqualone, you should not share needles as this can lead to the spread of infection.