Modafinil

Sounds like 'moe-daf-in-il'

Key points about modafinil

  • Modafinil is used to treat narcolepsy and other sleep disorders.
  • Modafinil is also called Modavigil®.
  • Find out how to take it safely and possible side effects.
Young man asleep in class with other students
Print this page

Modafinil is used to improve alertness for people with who experience extreme sleepiness during the day due to conditions such as narcolepsy. Narcolepsy is an ongoing condition with excessive daytime sleepiness that can interfere with night-time sleep. It may also cause sleep attacks, where you can suddenly fall asleep. 

Although there's no cure for narcolepsy, modafinil can help to control your symptoms. Modafinil increases alertness and reduces excessive sleepiness during the day. Read more about narcolepsy.

Funding of modafinil in New Zealand

In New Zealand modafinil is funded under a 'Special Authority', for people who meet the criteria.

A special authority means your specialist will need to make an application to Pharmac (the government medicine funding agency) for approval before the medicine can be funded for you. This approval needs to be renewed every 24 months.

December 2024: Pharmac is removing the renewal requirements for modafinil.

This means that once special authority approval has been granted, it does not need to be renewed. Your doctor or nurse practitioner can continue to prescribe it. Previously, people needed input from a specialist every two years to renew their special authority. 

Read more: removal of the renewal criteria for stimulant treatments(external link).

In Aotearoa New Zealand modafinil is available as tablets (100 mg).

  • The usual dose of modafinil for adults is 1 tablet twice daily (in the morning and at noon), OR 2 tablets in the morning.  
  • Some people may be started on a lower dose – 1 tablet in the morning. 
  • Always take modafinil exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much to take, how often to take it and any special instructions.

  • Timing of your doses: You can take modafinil tablets with or without food, at about the same time each day. Swallow the tablets with a drink of water. Don't take your dose later than midday, or you may have trouble sleeping at night. 
  • Missed dose: If you forget to take your dose, take it as soon as you remember. But if it's nearly time for your next dose, just take the next dose at the right time. Don't take extra doses to make up for a forgotten dose. Don't take your dose later than midday, or you may have trouble sleeping at night. 

Here are some things to know when you're taking modafinil. Other things may be important as well, so ask your healthcare provider what you should know about.


Other medicines including contraceptives

Modafinil may interact with some medicines and herbal supplements, so talk to your doctor or pharmacist before starting modafinil or before starting any new medicines, including those you may buy over the counter. Some contraceptives may not work as well while you're taking this medicine. Talk to your healthcare provider if you are using hormonal contraceptives such as the contraceptive pill, implants, injectables and some intrauterine devices (IUDs). 


Modafinil can affect your concentration

Don’t drive a vehicle, ride a bike or operate machinery, including power tools, until you know how this medicine affects you. Limit or avoid alcohol as it can make these effects worse.


Pregnant or planning a pregnancy

Modafinil shouldn't be taken if you're pregnant. If you're taking modafinil, talk to your healthcare provider about suitable contraception. If you wish to become pregnant, ask your doctor about stopping modafinil. It shouldn't be taken for at least 2 months before pregnancy.

Like all medicines, modafinil can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.

Side effects What should I do?
  • Headache
  • Trouble sleeping
  • This quite common when you first start taking modafinil
    and usually goes way with time.
  • Tell your doctor if it continues.
  • Feeling sick (nausea) and being sick 
  • Stomach upset, indigestion, loss of appetite
  • Runny poo (diarrhoea)
  • Dry mouth
  • Tell your doctor if these bother you.
  • Anxiety, agitation, unusual behaviour or thinking, low mood, confusion
  • Changes in vision
  • Migraine
  • Strange or uncontrolled movements
  • Chills, sweating, tingling or numbness
  • Tell your doctor or ring Healthline 0800 611 116. 
  • Chest pain, fast heartbeat, or shortness of breath
  • Tell your doctor immediately or ring Healthline 0800 611 116. 
  • Allergic reaction such as skin rash, itching, swelling of the lips, face, and mouth or difficulty breathing such as chest tightness, or wheezing
  • Tell your doctor immediately or ring Healthline 0800 611 116. 

Read more about medicines and side effects and reporting a reaction you think might be a side effect.

Brochures

Medicines and side effects [PDF, 91 KB] Healthify He Puna Waiora, NZ, 2024
Modafinil(external link) New Zealand Formulary Patient Information
Modavigil(external link) Medsafe Consumer Information Sheet
5 questions to ask about your medications(external link) Health Quality and Safety Commission, NZ English(external link), te reo Māori(external link)


References

  1. Modafinil(external link) New Zealand Formulary

Brochures

Medicines and side effects
Healthify He Puna Waiora, NZ, 2024

5 questions to ask about your medications

5 questions to ask about your medications

Health Quality and Safety Commission, NZ, 2019 English, te reo Māori

Free helplines

Healthline logo

Text 1737 Helpline logo

Logo with link to Māori Pharmacists website

Credits: Sandra Ponen, Pharmacist, Healthify He Puna Waiora. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Angela Lambie, Pharmacist, Auckland

Last reviewed: