As of November 2012, modafinil is the only drug approved by the Air Force as a "go pill" for fatigue management.
If the flight is long enough where alertness is an issue, or if the flight occurred during periods where the aircrew would normally have been asleep, we were sometimes issued Dexedrine tablets to take to help remain awake and alert.
In the USAF, three sleep aids (temazepam aka Restoril, zolpidem aka Ambien, & zaleplon aka Sonata)and two stimulants (dextroamphetamine aka Dexedrine & modafanil aka Provigil) are approved for use by certain aircrew in particular operational situations.
“It works for 48 hours or so, but eventually you need to sleep.” Perhaps the most remarkable thing about modafinil is that users don't seem to have to pay back any “sleep debt”. Normally, if you stayed awake for 48 hours straight you would have to sleep for about 16 hours to catch up.
The present study demonstrates that modafinil is a safe and effective fatigue countermeasure for use by pilots during military flight operations. Few side effects were reported, during both ground testing and operational use.
In the UK and Australia, modafinil can only be legally obtained with a prescription. Besides, some online pharmacies may also require an Rx for the “smart drug” even if they operate in a jurisdiction in which it's not required.
In the United States military, modafinil has been approved for use on certain Air Force missions, and it is being investigated for other uses. As of November 2012, modafinil is the only drug approved by the Air Force as a "go pill" for fatigue management.
Modafinil may cause some people to feel dizzy, drowsy, have trouble thinking or controlling movements, or trouble seeing clearly.
Like other stimulants, modafinil increases alertness and energy by activating certain responses in the CNS. Provigil or modafinil begins to work within 30 to 60 minutes after it's taken and may take slightly longer to kick in if taken on a full stomach.
The warning to the pilots from the FAA doctors says Viagra may impair pilots' ability to distinguish between blue and green, important for runway lights and instrument panels.
The medications which Pilot prescribes for erectile dysfunction are called PDE5 inhibitors. These male enhancement pills work by increasing penile blood flow by targeting the enzyme responsible for the contraction of blood vessels.
Pilots and air traffic controllers should not use Viagra within 8 hours of performing their (aviation) duties. Levitra, approved by the FDA in August 2003, has a similar profile to Viagra. The FAA initially allowed the use of Levitra in pilots/controllers.
Managing fatigue is a challenge, particularly when flying overnight (red-eye) flights. Some countries allow pilots to take controlled naps to improve alertness during the landing. So far, the U.S. has not allowed this fatigue mitigation. Pilots keep flight deck lights up, and engage in conversation to help keep alert.
 Take Advantage of Naps
A 20-30-minute map is all you need to help fight pilot fatigue. A short burst of rest will help to improve alertness in your day. However, you want to be sure your nap isn't too long.
Controlled Rest in Flight for Pilots
The principle of controlled rest is to allow the pilots to boost alertness and energy. It's the equivalent of a “power nap”. Ideally controlled rest should be between around 10 – 20 minutes as this limits you to the lighter stages of non-rapid eye movement (NREM) sleep.
Modafinil is a much milder stimulant than Adderall, and its mild stimulant properties allow for using it in varied situations to address lethargy and sleepiness without the potential for inducing anxiety, jitteriness, irritability, or agitation.
Use as a doping substance
Modafinil is on the World Anti-Doping Agency (WADA) list of banned substances and it is classified as a stimulant [3]. Its effect on performance has been researched only little, but based on its effects it is believed to improve endurance and explosiveness.
Morning-dosed modafinil promotes nocturnal sleep, normalizes sleep architecture, and decreases daytime sleepiness in abstinent cocaine users. These effects may be relevant in the treatment of cocaine dependence.
Although modafinil is a highly effective prescription medication, it has the same effect on dopamine centers of the brain as cocaine, methamphetamine, and amphetamines do. Like other stimulants, it also causes psychoactive and euphoric effects, which influence a person's moods, thoughts, emotions, and perceptions.
Modafinil is a wakefulness-promiting agent used to treat sleep disorders, while ritalin is often used to treat ADHD and narcolepsy. Both drugs are commonly used off-label as so-called “smart drugs” to improve cognitive function.
A dose of modafinil is about as strong as 600mg of caffeine [2] the equivalent of about two grande coffees, but does not induce the shakiness, feelings of anxiety, or frequent trips to the bathroom that excessive caffeine can.
Pharmacological treatment
These drugs are usually taken shortly before a flight. They include: Anti-anxiety medication, such as diazepam (Valium) or alprazolam (Xanax). Motion sickness medication, such as dimenhydrinate (Dramamine).
Attention-Deficit/Hyperactivity Disorder ( ADHD ), formerly called Attention Deficit Disorder ( ADD ), and medications used for treatment may result in cognitive deficits that would make an airman unsafe to perform pilot duties.
Anti-Depressants / Anxiety – Single-use Anti-Depressants such as: Celexa (Citalopram Hydrobromide), Lexapro (Escitalopram Oxalate), Prozac (Fluoxetine Hydrochloride), Zoloft (Sertraline Hydrochloride).