Sleep disorders are the disorders where your sleep is constantly disturbed or deviated from your natural pattern and can lead to serious interference in your day to day functioning. Some common sleep disorders include obstructive sleep apnea (irregular breathing during sleep), narcolepsy (irregular sleep patterns leading to sleepiness during daytimes) and cataplexy (loss of muscle tone when you awake), etc.

Effective treatment and management of these disorders are essential to ensure that you go about your personal and professional life peacefully.

Modafinil and Adrafinil are drugs that have been introduced in the market especially to treat and cure the above-mentioned sleep disorders. They are known as Eugeroic drugs in the market. The basic composition of these drugs, as well as their mechanism of action, is quite similar to each other. However, there are certain things that set them apart too.

Let us take a look at these drugs in detail.

Adrafinil vs Modafinil Comparison Chart

Below is a comparison chart comparing Modafinil with Adrafinil to give you some brief specifications of each drug.




Year Introduced



Drug Category



Half Life (Effect lasting time)

5 hours

11-13 hours


To treat sleep disorders.

To treat Narcolepsy, sleep disorders.


Typical dosages are 300mg and 600mg in a day.

Typical Dosages – 100mg and 200mg.

Method of Intake



Side effects

Headache, nervousness and can lead to heart issues if taken over a long period.

General side effects include dizziness, nausea, headache, and nervousness.




Availability of Generic Version



Format Available




Cephalon Inc

Cephalon Inc

Summary- What is Modafinil and Adrafinil?

Modafinil and Adrafinil both are primarily used to treat sleep-related disorders such as obstructive sleep apnea, narcolepsy, etc. by activating the concerned areas in the brain (hypothalamus and amygdala) and increasing the dopamine levels to improve alertness and wakefulness so that you can have a normal day with a peaceful sleep.

Modafinil as a compound has been effective in restoring normal sleep patterns by interacting with the neurotransmitters in the brain.

Specifically, they interact and active the neurons in the brain and increase dopamine levels.Unlike brain stimulants, they do not increase the dopamine release levels however Modafinil increases the availability of dopamine by blocking the receptors that block dopamine.


This way, you stop feeling sleepy or groggy throughout the day and also manage to catch a good night’s sleep.

Adrafinil is known as the precursor of Modafinil. It contains an extra hydroxyl group when compared to Modafinil.

Once you take Adrafinil tablets, it gets converted into Modafinil in the liver while the remaining portion becomes the inactive modafinilic acid.

Hence, the composition of Modafinil and Adrafinil along with the mechanism of action remains the same.


Modafinil and Adrafinil Uses

When you compare the usage of Adrafinil vs Modafinil, you will realize that the primary usage for both Adrafinil and Modafinil is the treatment of sleep disorders. You will find them quite effective in keeping you awake, helping you avoid irregular sleep at day times as well as in handling fatigue.

Clinically, it has been arrived at that this class of drugs, that is, Eugeroics find more usage in reducing the urge to sleep with a prolonged period of sleepiness.

In addition to being used to treat the sleep-related disorder, Adrafinil has also found usage in improving stamina, attention and energy levels, especially among shift workers. The increased stamina and reduced sleepiness leads to productivity, which is why most of the corporate workers also use this.

Similar to Adrafinil, though Modafinil is FDA approved to treat sleep disorders, it is also used to improve alertness off-the-label. Modafinil is also used to bring out energy and happiness as it elevates histamine and dopamine levels in you.

Adrafinil vs Modafinil Efficiency

Adrafinil vs Modafinil

Even though Modafinil and Adrafinil have a similar composition and mechanism of action, when we compare the efficiency of Adrafinil vs Modafinil, it is found that Modafinil is very effective when compared to Adrafinil.

This significant difference in potency is due to the fact that not the entire compound of Adrafinil gets converted to Modafinil during ingestion. Some of the compound gets converted into inactive substances hence requires higher dosages to achieve the level of efficiency of lower dosage Modafinil.

This is the reason that you will have the same effect when you take Modafinil the dosages would range from 100 to 200mg while for Adrafinil it is not uncommon that the dosages go up to 600-1200mg per day.

Also, since there is no intermediate process required for Modafinil to action, the reaction time for Modafinil is also less. On the other hand, Adrafinil needs to be metabolized by the liver before it can take effect. Modafinil reaches its peak in blood levels within 90minutes while Adrafinil requires up to 150 minutes for the same.

On the other hand, if we consider the efficiency of Modafinil or Adrafinil regarding their cognition enhancing abilities, we will understand that they are quite similar in efficacy for this treatment. They have the capacity to increase memory power, executive functions, as well as reduce fatigue due to exertion.


Modafinil and Adrafinil Dosage

Modafinil is the primary drug that is used to treat sleep disorders. The typical dosage for Modafinil is either 100mg or 200mg per day. You can either take one tablet 12 hours before you would sleep or taken any time in the day at intervals. This dosage can help you control for most sleep disorders such as narcolepsy, obstructive sleep apnea, etc. and keep you alert for 6-8 hours a day.

Adrafinil, on the other hand, comes in stronger dosages. You are recommended to take at least 150mg – 300mg as it generally works in higher doses. You can start small and then increase gradually. Also, please note that this needs to be taken in cycles to avoid any negative side effects. Also, please ensure that this should not be taken more than three times a week.

Side effects

The side effects of both these Eugeroic drugs are similar due to the similarity in compositions. The most common one that you are most likely to experience is dry mouth, insomnia due to excessive dosage and headache related effects. These are generally brief in nature and go over a period of time.

Some serious side effects have been reported in isolation for both these drugs, such as heart rhythm fluctuation, blood pressure issue, etc. These are rare instances and are commonly due to the fact that that recommended period of usage has been extended to the drugs.

When it comes to Adrafinil vs Modafinil, Adrafinil has the most serious side effect of both these drugs. Adrafinil as a process is metabolized in the liver first before it takes action in the brain. Due to this, some studies have found that when you take Adrafinil over a period of time, it may affect the liver.

In the case of Modafinil, the most serious side effects encountered are skin rashes, blisters, sore mouth, fever, etc. It also has a chance of inducing heart related ailments such as increased heart rate, blood pressure, etc. Hence, you should think twice before using Modafinil if you have a history of heart disease.


Modafinil is a compound that does not have any direct interaction with the brain neurons and is only acting as a brain stimulant to improve the alertness or wakefulness in you. Hence, the chances of you experiencing any withdrawal symptoms for Modafinil are very slim. There might be a slight effect on the sleep patterns and activeness. However, the same will be set right over the due course of time.

The withdrawal effects for Adrafinil will also be similar to Modafinil however if we compare them in the case of cognitive enhancement, you are likely to feel the strain coming back once you stop using Adrafinil or Modafinil. This must not be attributed to withdrawal symptoms, however; this is the effect of the drug wearing off and the brain neurotransmitter levels returning back to normal.

Popularity or abuse

In the battle of popularity between Adrafinil vs Modafinil, there are some conflicting results. Though most of you would prefer to opt for Modafinil as it is a more potent drug and would react and act faster, there is also a preference for Adrafinil as it is similar to Modafinil and also easily accessible in the market without a prescription. Currently, the sale of Adrafinil is discontinued by Cephalon, and it is only available via some Chinese suppliers.

Both Adrafinil and Modafinil have very less abuse potential since they do not provide any high or sense of euphoria when taken for any purpose. Due to their lack of immediate reaction to the hormones, one would not expect that these drugs would be consumed from an abuse point of view. However, they are indeed habit-forming drugs, and one must not be taken them beyond the prescribed dosage and routine. Adrafinil is currently unregulated by the FDA. However, Modafinil is classified as a Schedule IV substance and cannot be bought without a prescription.


The drug Modafinil is very expensive and is Provigil’s generic version. The cost for a 30 day supply of Modafinil will be somewhere around 150- 300$ depending on the dosage that has been prescribed.

Adrafinil is known to be available at a fraction of the cost of Modafinil and typically costs 30$- 120$ depending on the dosage on all retail and online shops.

Recap(differences and similarities)

Modafinil and Adrafinil are drugs that are majorly used to treat sleep disorders and have almost identical compositions and mechanism of action. Chemically speaking, there is only one difference in the composition of Adrafinil and Modafinil which is a hydroxyl group present in Adrafinil.

Adrafinil is known to be a prodrug to Modafinil which means that it needs to get converted to Modafinil upon ingestion. Once you have taken Adrafinil, it is metabolized in the liver, and a portion of it gets converted to Modafinil for action, and other gets converted to modafinil acid which is an inactive compound. Due to this reason, Adrafinil is considered to less potent that Modafinil as only a part of the drug gets converted to the active agent.

This activity of metabolism is also known to cause strain on the liver.

Both these drugs are found to be quite effective when it comes to treating narcolepsy and enhancing your cognitive function however Modafinil is found to be the more effective of the two.

Adrafinil and Modafinil have certain side effects and it is advised that in the case of rashes, skin allergies while taking Modafinil and heart pressure issues while taking Adrafinil you must immediately stop the medication and consult your physician.

The major differences in both these drugs are their cost and dosages. A typical dosage for Modafinil is 100-200mg a day while it may vary up to 600-1200mg per day for Adrafinil due to the relative efficacy.

Modafinil is also expensive while compared to Adrafinil with a 30-day supply coming to 300$ in comparison to Adrafinil’s 30$-120$ range.

Making a Choice

make your choice

Modafinil by nature is a sleep disorder treating drug which is known to be the most effective in this class. Adrafinil is a prodrug for Modafinil, which means it needs to be converted to Modafinil in your bloodstream to start to have an effect.

In case you have any previous heart issues, it is imperative that you consult a physician before taking both Modafinil and Adrafinil. Regarding potency, Modafinil is more efficient than Adrafinil since it can directly start showing effect without having the need to be metabolized. Hence, in conclusion, it is recommended that Modafinil is the effective choice for sleep-related disorders however if cost is a concern, you can surely consider Adrafinil also.