Why You’re Irritable On Modafinil & How to Manage It

Do you find yourself easily irritated when you take Modafinil? Does it feel as though your patience for people has reached an all-time low? You’re not alone.

While Modafinil is an excellent productivity enhancing drug, irritability can be an undesirable side-effect. It can become an issue when you’re at work or school and need to interact with people throughout the day.

Here’s why Modafinil can make you feel this way, and how to manage it effectively.

Where To Find Modafinil

Modafinil is a prescription-only medication. Doctors will only prescribe it for a confirmed diagnosis of ADHD, narcolepsy, or sleeping issues associated with shift work. Outside of this scope, it’s nearly impossible in most countries to get Modafinil at your local pharmacy.

Online vendors, however, operate very differently.

Modafinil falls into a legal grey area, allowing users to buy it online without a prescription.

Learn more about buying Modafinil in Australia, Canada, Singapore, The UK, and Ireland.

There are many different online vendors in the Modafinil space, however, many of them are unreliable. It can be a bit of a gamble to know whether you’re going to receive your order when you make your purchase.

We recommend Afinil.com as the best source of Modafinil online.

They’re one of the few companies we’ve found that delivers their product on time and actually respond to customer service questions. They have a great selection of generic Modafinil and available discount options. They offer free shipping and guarantee delivery to most countries.

Buy Modafinil Online

What Makes Us Irritable?

In order to understand why Modafinil can make us feel irritable, we need to discuss WHAT irritability actually is.

We have a natural threshold for tolerating stress. When we’re fed, healthy, and well-rested this threshold is high. This means we can easily tolerate small annoyances or frustrations and are much better at shrugging them off throughout the day.

As soon as we become tired, like after a poor night’s rest or at the end of a long workday, our threshold for this tolerance becomes much lower. We become more irritable and reactive to stressors in our environment.

You may be wondering if Modafinil makes us feel more awake, shouldn’t it INCREASE our tolerance for these types of things?

You would be correct in assuming this, except for one thing… Modafinil makes us FEEL more awake, but it doesn’t actually give us the same benefits of a full night’s sleep.

It also doesn’t protect us from nutritional deficiencies or the impacts of long-term stress.

What Causes of Irritability?

  • Fatigue
  • Hypoglycemia (Low blood sugar)
  • Long-term Stress
  • Anxiety
  • Depression
  • Sleep deprivation
  • Cold/Flu
  • Metabolic conditions
  • Caffeine or nicotine withdrawal

How Modafinil May Cause Irritability

There isn’t just one reason why Modafinil can cause users to feel irritable. There are in fact a few different ways Modafinil can produce this effect.

1. Sleep Deprivation

The main function Modafinil has on the human body is to promote the feeling of wakefulness. Therefore, one of the main side effects of the medication is insomnia.

For more information on this, check out our article on the side effects of Modafinil and how to avoid them.

There have been numerous studies looking at the effects sleep deprivation has on the body, and nearly all of them have shown mood disturbances (like irritability) as one of the main side effects [2].

There Are 3 Ways Sleep Deprivation Is Classified:

  1. Long-term total sleep deprivation, defined as an absence of sleep for over 45 consecutive hours.
  2. Short-term total sleep deprivation, defined as an absence of sleep for less than 45 consecutive hours.
  3. Partial sleep deprivation, defined as restricted sleep habits to less than 7 hours of sleep every 24 hours.

Modafinil users often experience either partial or short-term total sleep deprivation. In some cases, long-term total sleep deprivation may occur.

The longer sleep is avoided, the more likely it is that you’ll begin to experience side effects like confusion, depressive symptoms, difficulty focusing, and irritability.

How To Manage Sleep Deprivation On Modafinil

The best way to avoid insomnia and sleep deprivation on Modafinil is to ensure you’re taking your Modafinil early in the day. The effects of Modafinil will last anywhere between 10 and 14 hours. This means that you will need to take the Modafinil at least 10 hours before your intended bedtime.

If you’re finding that the effects of Modafinil are lasting a long time and is keeping you up at night, it may be necessary to lower the dose, or only take every second or third day.

It’s important that we sleep 7 hours or more every night. It’s not a good idea to push yourself too hard by avoiding sleeping. Especially for more than 24 hours.

Sleep deprivation will have NEGATIVE effects on your productivity if it goes on for too long. For most of us, this defeats the whole purpose of taking the drug in the first place.

2. Nutrient Deficiencies

Nutrient deficiencies are major causes of irritability in humans [3]. One of the main reasons this happens is because as we become depleted in nutrients, our ability to respond to various stressors in our environment begins to decrease. When we’re unable to manage stress, it can make even small things seem like big issues, causing us to overreact emotionally.

Modafinil offers no nutritional support. This is important to remember because nutritional deficiencies among Modafinil users are all too common.

Modafinil can affect our nutrient status in 2 ways:

A. It Lowers Our Appetite

One of the most common side effects of Modafinil is a low appetite. This is because Modafinil targets the sympathetic nervous system (SNS) which works to inhibit the processes involved with digestion and appetite.

Modafinil users often report going all day without remembering to eat.

One day of fasting (going without food) isn’t an issue for most people. Our body has enough nutrient stores to function without for a few days.

With regular use, however, it won’t take long for our stores of essential vitamins and minerals to run dry, causing further changes to our neurological balance.

Low carbohydrate intake can also cause problems with neurotransmitter production.

One of the main ways this happens is through insulin transport pathways. We use insulin to transport carbohydrates into the cells to be used as energy. Insulin is therefore triggered by carbohydrate intake. It’s also required for the transport of tryptophan into the brain where it’s made into serotonin. This is one of the most important neurotransmitters in our brain. One of its key functions is to regulate appetite.

If we don’t eat enough carbohydrates to elevate insulin levels, tryptophan is unable to pass the blood-brain barrier and can cause a drop in overall serotonin production. [4].

B. It Can Actively Deplete Essential Nutrients

Modafinil is a stimulant, which means it “turns on” the central nervous system. Neurotransmitter and hormone production ramps up, which requires the use of minerals and vitamins as cofactors to drive these reactions.

Modafinil increases orexin, norepinephrine, dopamine, cortisol, and histamine production. When this happens, we quickly burn through micronutrients like magnesium, B vitamins, and zinc.

Amino acids are also important, including L-Tryptophan and L-Tyrosine. These serve as precursors to dopamine, norepinephrine, serotonin, and the sleep-regulating neurotransmitter, melatonin.

When we burn through these nutrients, other parts of the body that also rely on these nutrients will start to be affected as well. Other processes like blood & immune cell production, muscle contraction, nerve impulses, and digestion can all be affected.

If we’re depleted in these nutrients, we can become more emotional and unable to manage stress as effectively, resulting in irritability.

How To Manage Nutritional Deficiencies On Modafinil

The best way to avoid problems with micronutrient depletion on Modafinil is to ensure we’re eating enough high-quality food throughout the day. This is important even if we don’t feel hungry.

Try taking nutritious snack bars with you to work or school and setting an alarm on your phone for every 3 hours to remind you to eat.

For breakfast and dinner, when the effects of Modafinil aren’t as intense, it’s important to make sure you’re eating enough green, leafy vegetables and proteins. These types of foods contain the bulk of our nutrient requirements.

Nutritional supplements can also be very helpful, especially if taking Modafinil on a regular basis.

The Key Nutrients To Pay Attention To For Irritability:

  • Magnesium
  • B complex vitamins (especially B6, B9, and B12)
  • Zinc
  • L-Tyrosine
  • L-Tryptophan
  • Phosphatidylcholine
  • Omega-3-fatty acids (such as fish oil)

3. Neurotransmitter Imbalance

Modafinil has an indirect effect on serotonin levels through its dopamine boosting effects. These 2 neurotransmitters work closely together, opposing each other in many of their effects.

When dopamine levels rise, it causes serotonin levels to decrease. When this happens, irritability and other mood disturbances become common.

Another neurotransmitter Modafinil affects is GABA. This is the main inhibitory neurotransmitter in the brain. It functions as the “brake pedal” for the nervous system, slowing it down when it’s time for our body to relax, sleep, or digest a meal. This is one of the main reasons why we feel tired and sluggish after a particularly large meal.

Without enough GABA, we can start to develop issues with our ability to resist stress. This leads again to irritability.

How To Support Neurotransmitter Levels on Modafinil

Supporting neurotransmitter levels on Modafinil starts with nutritional support, as outlined in more detail in point number 2.

There are other supplements and techniques we can use that are more specific to neurotransmitter levels, including:

  • Supplement GABA in the evenings
  • Supplement 5-HTP in the morning/early afternoon
  • Ensure adequate carbohydrate intake throughout the day
  • Practice meditation to boost GABA levels
  • Take occasional breaks from Modafinil use
  • Drink at least 2 liters of water per day
  • Drink herbal teas that boost GABA (such as Chamomile, Ginkgo, or Kava)
  • Supplement with L-Theanine

Summary Of Avoiding Irritability On Modafinil

There are many different ways Modafinil can contribute to irritability. This includes direct AND indirect effects including nutrient depletion, neurotransmitter imbalances, and sleep deprivation.

The best ways to avoid irritability starts with the responsible use of Modafinil. You should always aim to eat a well-balanced nutritional diet with enough carbohydrates throughout the day. Eating the right fuel will provide your body with the macronutrients like B vitamins and magnesium needed to support your neurotransmitters.

It may be helpful to supplement some of these more specific micronutrients to make sure you don’t burn through them too quickly. The primary examples include vitamin B6, B12, zinc, and magnesium.

Other supplements like L-Theanine, 5-HTP, and GABA can be beneficial in keeping your neurotransmitters within balance.

Meditation can significantly help to boost both serotonin and GABA levels and may lower the chances of sleep deprivation. It’s also useful to take your Modafinil early in the morning or perhaps reduce the dose if insomnia becomes a problem for you.

Overall, the effects of Modafinil can significantly enhance your workflow and productivity, but won’t protect you from other health issues. For this reason, it’s important to maintain a focus on overall health and nutritional status, with a particular focus on neurotransmitter balance when taking Modafinil regularly.  This is going to allow you to get as much out of your Modafinil as possible.

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  1. Durmer, J. S., & Dinges, D. F. (2005, March). Neurocognitive consequences of sleep deprivation. In Seminars in neurology (Vol. 25, No. 01, pp. 117-129). Copyright© 2005 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA..
  2. Murray, E. J. (1965). Sleep, dreams, and arousal.
  3. Balint, J. P. (1998). Physical findings in nutritional deficiencies. Pediatric Clinics of North America, 45(1), 245-260.
  4. Fernstrom, J. D., & Wurtman, R. J. (1971). Brain serotonin content: increase following ingestion of carbohydrate diet. Science, 174(4013), 1023-1025.

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