Summary
Product name often used: Provigil. The active molecule is modafinil.
Common tablet strengths supplied in the United Kingdom are 100 mg and 200 mg.
Typical licensed uses include treating excessive daytime sleepiness linked to narcolepsy, persistent sleepiness due to obstructive sleep apnoea when used in addition to primary therapy, and shift work sleep disorder when a clinician judges it appropriate.
If you want more on adverse events see Safety and realistically possible unwanted effects warning bulletins. For legal and supply details in the UK go to Status of legality and regulatory rules.
The Mode By Which It Acts in the Brain
Modafinil affects several neurotransmitter systems, including dopamine, norepinephrine, glutamate paired with the orexin network. The exact the mechanism of action is not fully defined, but the medicine reliably promotes wakefulness and reduces pathological sleepiness without the strong euphoria typical of some amphetamine stimulants.
Because responses vary, clinicians usually individualise the the dose and its timing. See practical guidance in Dose amount and instructions for taking.
How to take pills safely this dose Modafinil
Always follow the directions from your prescriber. Do not change the dose or stop treatment abruptly without medical advice.
- Most adults start with 200 mg once daily for common signs that point to.
- For narcolepsy and ongoing sleepiness in obstructive sleep apnoea, the dose is usually taken in the morning.
- For shift work sleep disorder it is commonly taken about one hour before the work shift starts.
- People with liver impairment, the elderly or those who are frail may begin at 100 mg and have the dose adjusted as needed.
Modafinil may be taken with or without food. A heavy meal can delay the time to onset for some people, so adapt timing to suit your routine. Duration of treatment varies: some patients use it short term while others remain on it with periodic review.
Safety reminders Before you kick off
Do not take modafinil if you have had a previous allergic or severe skin reaction to modafinil or armodafinil.
Tell your doctor if you have any history of the following:
- Cardiac conditions such as chest pain, recent heart attack, uncontrolled high blood pressure or structural heart disease
- Significant liver disease, including cirrhosis, or marked kidney impairment
- Mood disorders, psychosis, severe anxiety or prior substance misuse
- Current medicines that affect blood pressure or cardiac rhythm
- Plans for pregnancy, current pregnancy or breastfeeding
Severe cutaneous reactions are uncommon but may be life threatening. Stop treatment and seek urgent assessment if you notice rash, blistering, peeling skin, mouth ulcers, facial swelling or difficulty breathing. See Unintended effects and caution flags for additional information is provided.
Modafinil can change mood and cognition. Until you know your response, avoid driving or operating heavy machinery; reassess fitness to drive once your response is stable.
Medication dose was not taken and Overdosing episode Concerns Advice
If you forget a morning dose and it is still early in the day you may take it; if it is late or close to bedtime, skip that dose to avoid insomnia. Never double up to compensate for a i forgot to take a dose.
In the event of an overdose seek emergency medical attention. Symptoms can include severe agitation, marked anxiety, prolonged insomnia, rapid pulse, high blood pressure, shaking, confusion or hallucinations.
Drug Interaction Safety protocols and Special Safety protocols
- Spirituous beverage: mixing alcohol with modafinil can increase unfavorable effects or unpredictably alter alertness. Avoid alcohol while being treated if possible.
- Hormonal contraception: modafinil can reduce the effectiveness of combined oral contraceptives and some other hormonal methods via enzyme induction. Use a reliable non-hormonal back-up while on treatment and for about two months after stopping.
- Enzyme-metabolised medicines: modafinil affects CYP3A4 and CYP2C19 and may interact with certain antifungals, antiepileptic medicines, some antidepressants and warfarin. Have your clinician or pharmacist review all medicines and supplements you take.
- Tasks needing full alertness: until you are sure modafinil does not impair you, be cautious with driving and other potentially dangerous activities.
For urgent concerns about engagement and communications span conversations, gestures, and feedback. or temporary side effects see Possible adverse ramifications and warning signs.
Undesired reactions and When to Reach Out for Help
Seek immediate emergency care if you have signs of a severe allergic reaction such as a widespread rash, swelling of the face, lips, tongue or throat, or difficulty breathing.
Stop modafinil and contact your prescriber urgently if you experience any of the following:
- New rash, mouth ulcers or peeling skin
- Significant mood or behaviour changes including new or worsening depression, agitation, aggression, hallucinations or thoughts of self harm
- Chest pain, trouble breathing, or a very rapid or irregular heartbeat
- Fever with swollen glands, dark urine, leg swelling or yellowing of the skin or eyes
More common, typically mild unintended consequences include:
- Pulsating head pain or light headedness
- Nausea plus gastrointestinal discomfort or diarrhoea
- Nervousness, jitteriness or anxiety
- Difficulty obtaining restful sleep
- Lumbar ache, dry mouth, nasal congestion and reduced appetite
This list is not the full list. If you are concerned about any symptom ask your pharmacist or prescriber for advice.
Other forms of treatment and How They See which one is better
Depending on the diagnosis and your medical history, clinicians may recommend other medicines or non-drug approaches. A brief comparison follows.
- Armodafinil (Nuvigil in some countries): the R-enantiomer of modafinil. Many patients report a similar wakefulness effect with subtly different duration.
- Pitolisant (Wakix): works through histamine H3 receptor inverse agonism. It is a non-stimulant option and may benefit cataplexy in some patients.
- Solriamfetol (Sunosi): a norepinephrine and dopamine reuptake inhibitor used for excessive daytime sleepiness in narcolepsy and OSA. It is often supplied by specialist services and tends to be more costly than generic modafinil.
- Methylphenidate, dexamfetamine and lisdexamfetamine: stimulant plan B routes sometimes used for severe hypersomnolence. They require cardiovascular assessment and are subject to stricter prescribing controls.
- Non-drug measures: optimising treatment for any underlying sleep disorder (for example correct CPAP use in OSA), improving sleep hygiene, scheduled naps, light therapy and controlled caffeine use can all help.
Choice of treatment will depend on diagnosis, coexisting health conditions, side effect profile and realized potential drug contact and response alerts such as effects on contraception. Discuss options with a sleep specialist or your treating clinician.
Prices for goods in the UK and Stock Status
Prices vary by pharmacy, brand versus generic, and whether you have an NHS prescription. The figures below are approximate and expressed in Great British Pounds (GBP).
- NHS prescriptions in England: the standard charge per item is approximately 9.35 GBP (subject to change). Prescriptions are generally free in Wales, Scotland and Northern Ireland for eligible patients.
- Private prescription for generic modafinil: retail prices might be roughly 1.00 to 3.00 GBP per 200 mg tablet, equating to around 30 to 90 GBP for 30 tablets.
- Private prescription for brand-name Provigil: typically higher, perhaps 2.00 to 6.00 GBP per 200 mg tablet (about 60 to 180 GBP for 30 tablets).
- Armodafinil prices may be similar to or slightly above generic modafinil.
- Specialist medicines such as solriamfetol or pitolisant usually cost more and are often dispensed via hospital or specialist pharmacy routes.
When dispensed on the NHS in England your personal cost is normally the standard prescription charge per item, independent of the actual list price, subject to exemptions. Private pharmacies set their own prices and may add a dispensing fee.
If ordering from online pharmacies ensure they are GPhC registered and test the system for genuine packaging. Importing prescription medicine for personal use without correct documentation risks seizure by Border Force. See Status in law and regulatory guidelines to get more detail.
Legal standing and regulatory requirements in the UK
- Modafinil is a Prescription Only Medicine (POM) in the UK under the Human Medicines Regulations 2012; a valid prescription is required to lawfully obtain it.
- It is not classified as a controlled drug under the Misuse of Drugs Act, but supplying or selling it without a prescription is illegal.
- Online pharmacies based in the UK must be registered with the General Pharmaceutical Council (GPhC). Look for the GPhC mark and confirm registration on the GPhC website before ordering.
- Importing prescription medicines for personal use without appropriate paperwork can lead to seizure and other issues at the border. Carry prescriptions and supporting documentation if bringing medication into the UK.
- Driving: if your sleep disorder affects alertness you may need to notify the Driver and Vehicle Licensing Agency (DVLA). Do not drive until your condition and treatment meet the legal fitness to drive requirements.
- Sport: modafinil is prohibited in competition by the World Anti-Doping Agency. Athletes should seek a Therapeutic Use Exemption if use is clinically justified.
For practical safety while taking modafinil see Conversational intercommunications among teammates fuel progress. Among Drugs and Handling Preventive steps and Secondary reactions and warning signs.
Express FAQs
Can I take modafinil with food? Yes. Food does not usually change the total amount absorbed but may delay onset for some people.
How long will I need treatment? This varies. Many patients are reviewed every few months to confirm benefit and dose.
Can I stop suddenly? You should not stop unexpectedly without advice from your prescriber. A gradual reduction may be advised after long term use.
Is it acceptable to use while pregnant? Data are limited. Discuss family planning, contraception and pregnancy in consultation with your clinician. If modafinil lowers the effectiveness of hormonal contraception see Interactions across networks Among Drugs and Protective Steps for guidance on back-up methods.
Core Points Overview and context
- The chief active ingredient is modafinil. Typical strengths: 100 mg and 200 mg tablets.
- Common adult dose: 200 mg once daily, with timing tailored to the condition being treated.
- Avoid alcohol and be careful with driving until you know how modafinil affects you.
- Stop and seek urgent medical review for any new rash or serious changes in mood or behaviour.
- In the UK modafinil is available only on prescription. Confirm online pharmacies are GPhC registered before ordering.
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