Centrally acting medication

Hypnotics

Temazepam has been used in military and civilian aircrew for the short-term treatment of insomnia associated with circadian rhythm disturbance for many years. Specific treatment should be directed towards other underlying causes of insomnia such as adjustment disorder. Temazepam is short acting and hangover effects are uncommon. However, drowsiness or light-headedness the next day, confusion, ataxia and amnesia are possible side-effects so the medication should be started for the first time when it is certain licence privileges will not be exercised the following day. Thereafter, it should be taken no less than eight hours before exercising licence privileges. Aircrew should not take temazepam continuously for more than one week because of the risk of dependency developing.

Zaleplon is also acceptable for medical certification subject to the same considerations as temazepam.

All other hypnotics, including zolpidem, zopiclone and “over the counter” preparations such as diphenhydramine and promethazine are disqualifying for medical certification.

Melatonin

Melatonin may be acceptable for certification if used short-term to aid in the treatment of jet lag.  It must be prescribed and taken under the direction of a treating clinician. Melatonin obtained online or overseas may not have undergone the same rigorous quality assurance processes and is not acceptable.

A review by an AME should confirm an absence of any significant side effects following a ground trial of the usual treatment dose for at least three consecutive nights.

Only immediate-release melatonin is acceptable for certification. Extended-release preparations are not licensed for the management of jet-lag and may cause more prolonged side effects, and as such are not acceptable for certification.  A dose of 3mg can be taken once daily for up to 5 days. The dose may be increased up to 6mg if necessary or reduced to 1mg if sufficient. At least 6 hours must have elapsed before flying. There is a maximum of 16 treatment courses per year.

Melatonin should only be taken as part of a broader plan to manage fatigue and it is not a replacement for other strategies. It should not be taken alongside other sleep medications, such as temazepam.

CNS stimulants

Modafinil is a central nervous system stimulant prescribed for narcolepsy and daytime sleepiness due to obstructive sleep apnoea. Common side-effects (>1:100) include anxiety, depression, dizziness and impaired concentration. Both obstructive sleep apnoea associated with significant daytime drowsiness despite CPAP treatment and narcolepsy are disqualifying and so any applicant taking this medication is unfit for flying duties.

Smoking cessation medication

Nicotine replacement therapy is acceptable.

Varenicline is a selective nicotine receptor partial agonist used for smoking cessation. Common side effects include drowsiness, dizziness and sleep disorder. Less commonly (1:1000 - 1:100) it can cause atrial fibrillation, palpitations, panic attacks, mood swings, incoordination, visual disturbance, myocardial infarction, anxiety, depression, irrational behaviour, psychosis and suicidal ideation. Varenicline is not compatible with aeromedical certification.

Bupropion is used for smoking cessation though its mode of action is unknown. Common side effects include anxiety, depression, dizziness and impaired concentration. Less commonly it can cause confusion and visual disturbance. Applicants are 'unfit whilst taking this medication.

Antidepressants

The SSRIs Sertraline, Citalopram, Escitalopram and Fluoxetine are the only antidepressants permitted for medical certification. The Depression flow chart offers further guidance. Citalopram and Escitalopram are associated with dose-dependent QT interval prolongation and should not be used in those with congenital long QT syndrome, known pre-existing QT interval prolongation or in combination with other medicines that prolong the QT interval. ECG measurements should be considered and electrolyte disturbances should be corrected before starting treatment. For Citalopram, the maximum daily doses are: 40mg for adults and 20mg for patients older than 65 years. For Escitalopram, the maximum daily doses are: 20mg for adults and 10mg for patients older than 65 years.

St John's Wort can be purchased without prescription and is used for the treatment of depression though it is not licensed for this purpose. It interacts with other medicines and the quality and quantity of active ingredient in the various preparations available is variable. An applicant or certificate holder on this treatment should be assessed as unfit and follow guidance in the Depression flow chart.

The half-life of Amitriptyline is 18 to 24 hours and active metabolites have a longer half-life. Sedation occurs at all dose levels. It is not compatible with medical certification even at the low doses used for treating neuropathic pain. The same applies to other tricyclic medications.

Antiepileptics and Medications for Neuropathic Pain

Epilepsy is disqualifying so these drugs are incompatible with medical certification. Gabapentin, Pregabalin and Carbamazepine prescribed for neuropathic pain and Valproate for migraine prophylaxis are disqualifying for medical certification because of the risk of unacceptable side effects.

Antipsychotic drugs

Antipsychotic drugs are not usually compatible with medical certification because the condition for which they are prescribed is likely to be disqualifying. However, low dose Sulpiride (less than 400mg daily) is acceptable for the treatment of Tourette's syndrome (unlicensed indication) provided a clinical report confirms treatment is successful without significant side-effects and a medical flight test gives a satisfactory result. The use of Clonazepam for treating tics is disqualifying.

Cannabidiol products

The use of cannabis, including any cannabidiol (CBD) derivatives, is not compatible with medical certification. This includes the use of any CBD products, whether prescribed or not.

Anxiety, insomnia, chronic pain, or addiction are among the common indications for using CBD products, each of which would normally mean an unfit assessment.

Whilst there is insufficient evidence to suggest that CBD products can impact on skilled task performance, the difficulties in isolating CBD from other psychoactive compounds, including tetrahydrocannabinol (THC), can result in non-negligible doses of these compounds being present in currently available formulations. This potential contamination also carries the risk of a positive drug screening test.