chemical structure/skeleton of modafinil molecule

Modafinil (2-[(diphenylmethyl) sulfinyl] acetamide) is a manufactured drug that is a Prescription Only Medicine in the UK. It is available on prescription for a number of sleep disorders, such as narcolepsy. Although it is legal to possess, supply is illegal without prescription.

Modafinil has also become increasingly used as a recreational drug. Many students and professionals use the drug to improve their productivity and focus, as well as staying awake for longer. It has therefore been likened to drugs such as Adderall, Vyvanese and Ritalin which have also been used recreationally by healthy individuals to improve concentration.

Modafinil comes in the form of a white tablet. Typically, the drug comes in dosages of either 100mg or 200mg. The suggested daily dose for the treatment of narcolepsy is between 100-400mg.

The majority of recreational users report using 200mg as their preferred dose, with a few using up to 400mg, and some excessive dosages being 1000mg and over.

Modafinil is now off-patent and is available with a number of licensed ‘branded generics’ with their own trade names. Provigil is the main UK trade name, but modafinil is also available worldwide with a range of trade names such as Modalert, Alertec and Modavigil.

Armodafinil is a stereoismer of modafinil and is often marketed alongside or in replacement of modafinil. They have similar effects and are taken at similar dosages.

Modafinil is a stimulant. The exact way in which modafinil works in the brain is still relatively unknown as it has a complex mechanism of action. However, it is known that it acts on a number of neurotransmitters. It has been shown that modafinil works primarily through noradrenaline and dopamine transporter inhibition. It also acts on serotonin, histamine, gamma-aminobutyric acid and glutamate. Increases in the hypothalamic release of histamine also occurs as a result of modafinil’s action on the orexin system.

Physiologically, modafinil increases blood pressure and resting heart rate.

The onset time of the effects of modafinil can be anywhere between 30 and 90 minutes. The effects reach its peak between 2 and 4 hours after ingestion and can last between 12 and 15 hours. The main effects have been likened to a very high dose of caffeine. It is reported to improve concentration, decision-making and planning, whilst dramatically reducing tiredness.

As it is a stimulant, users of modafinil can experience similar adverse effects to other stimulants. These can include:

  • insomnia
  • headache
  • paranoia
  • irritability
  • stomach aches
  • loss of appetite
  • nausea
  • diarrhoea
  • weight loss
  • blurred vision
  • dizziness

In rare cases, a high dose of modafinil can also cause psychosis.

However, despite its pharmacological similarity to other stimulants, it has been reported that these effects are not as serious as other stimulants.

Modafinil has been used to treat narcolepsy since the 1980s. Narcolepsy is a sleep disorder that is characterised by excessive daytime sleepiness. Unlike with other stimulants  the use of modafinil doesn’t seem to lead to rebound (hyper) sleepiness when stopped.

Nowadays, it is primarily used as a cognitive enhancer, but has also been used by the military and those who have sleeping problems due to irregular work shifts.

There is also an emerging body of evidence of its usefulness in treating cocaine addiction.

Lastly, it has been shown that modafinil could be useful in treating disease-related fatigue, attention-deficit disorder, Alzheimer’s disease, age-related memory decline, depression, idiopathic hypersomnia, cognitive impairment in schizophrenia and myotonic dystrophy. However, evidence for its usefulness in treating these disorders is not yet significant enough to warrant its widespread use for them.

Modafinil has a half-life of 12 -15 hours, with the drugs main effects peaking at around 2 – 4 hours and then lasting for around 12 hours or more. Therefore, if a user experiences adverse side-effects, it can be particularly uncomfortable as these are likely to last for a long duration.

As it is a sleep-inhibiter, users can also experience sleep insomnia. Prolonged periods of sleeplessness can cause increased stress and will impair immune functions. It can also increase the risk of cardiovascular disease, diabetes, metabolic syndrome and depression. There is also a link between sleep deprivation and bacterial infections in the blood because of dampened immune responses.

The possibility of addiction to modafinil has been doubted by some with only a few cases having been reported.

However, because modafinil acts on neurotransmitters such as dopamine, it has been suggested that addiction is possible with modafinil because of its mood-altering effects.

There have also been a few reports of users experiencing withdrawal symptoms such as poor concentration, sleepiness, low energy, depression, anxiety and shortness of breath. These are, however, rare and in most cases very mild.

Not much is known about the long-term effects of modafinil. However, it has been demonstrated that prolific and prolonged use of the drug could cause serious disruptions to the users sleep architecture.

It has also been shown to have the effect of increasing dopamine in the brain, which contributes to abnormal dopamine function when not taking the drug. This could have long-term implications by increasing the potential for the drug to be abused by vulnerable users.

These long-term effects can also occur when high doses are used regularly.

Mental Health

Modafinil can cause anxiety, paranoia and jitteriness. Because of this, those with mental health issues such as anxiety, depression or a history of psychosis should be extremely cautious when using it.

Dosage

As the effects of modafinil can last for over 12 hours, any adverse effects might last a long time and so can become particularly uncomfortable and harmful. It is therefore a good idea to start with a low dose to get a better idea of the level of the users’ tolerance.

Oral Contraception

It has been shown that modafinil can reduce the effectiveness of the oral contraceptive pill. This reduced effect can also last 1-2 months after taking modafinil.

Appetite

Modafinil can also cause a decrease in appetite. Users should therefore ensure they are eating consistently throughout the day, and it is especially important that you are keeping well hydrated because dehydration can cause loss of strength, stamina and the exacerbation of common symptoms of stimulants such as anxiety, headaches, jitteriness and dizziness.

Insomnia

In order to counter the possible effect of insomnia, it is best to take modafinil at least 8 to 10 hours before the user plans on sleeping to ensure the main effects have sufficiently worn off.

Impurities

It is also illegal to supply modafinil without a prescription. However, many sellers advertise modafinil for sale without a prescription. These sellers are unregulated and so it is not possible to guarantee that it will definitely be modafinil that is being sold. As a result, users should always test their drugs before using them.

‘It can make you smarter’

Modafinil cannot make the user smarter. In the last decade, many students and working professionals have started to use the drug to increase the amount of work they are able to complete.

There is some evidence that it increases working memory, the users’ ability to plan and to concentrate better, however this does not mean you will automatically become smarter. In fact, some users have reported that instead of having increased concentration on their work, they instead concentrate on certain distractions like watching videos or using social media and struggle to get back to concentrating on what they intended to do.

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