The safest rule is to take no medicine while flying, except on the advice of an authorised medical examiner. The condition for which the drug is required may be hazardous to flying. Specific drugs associated with aircraft accidents are:
- Antihistamines (widely prescribed for hay fever and other allergies).
- Tranquillizers (prescribed for nervous conditions, hypertension, and other conditions).
- Reducing Drugs (amphetamines and other appetite suppressing drugs can produce sensations of well being which have an adverse affect on judgement).
- Barbiturates, nerve tonics or pills (prescribed for digestive and other disorders, barbiturates produce a marked suppression of mental alertness).
Legitimate medications taken for minor ailments can jeopardise safe flight by their subtle or unpredictable effects on the pilot. This includes both prescribed medications and over-the-counter medicines.
Allergic Reactions: Some people may experience an exaggerated or allergic reaction to a medicine. The allergic response to a drug can arise unexpectedly and dramatically causing incapacitation.
Idiosyncrasies: An individual may react in an unusual and unexpected way to a particular medicine.
Synergistic Effects: When a drug is taken in combination with another drug the total effect may be exaggerated.
Effect of Drug Combinations: Two drugs taken at the same time can:
- Cancel each other out.
- Render each other more potent, or
- Cause a side reaction.
Drugs may have side effects which contribute to pilot error, and accidents. Some are listed below:
Antihistamines: Widely prescribed and readily available for sufferers of hay fever, allergies and colds. Drowsiness and dizziness are a common side effect. Decreased reaction time and orientation problems may occur.
Nasal Decongestants: Can cause nasal burning and stinging, sneezing and increased nasal discharge.
Aspirin: Side effects include, irregular body temperature, variation in rate and depth of respiration, hypoxia and hyperventilation, diarrhoea, gastrointestinal problems and decreased clotting ability of the blood.
Antacids: Allow the formation of carbon dioxide at altitude that can cause acute abdominal pain due to the distension of the stomach.
Sleeping Pills and Tranquilizers: Cause sleepiness, nausea, depression, reduced alertness, affected reaction time and concentration, visual disturbances, severe mental disturbances and predisposition to heat stroke.
Reducing Agents and "Pep" Pills: Drugs generally containing amphetamines. They produce a feeling of high spirits and false confidence, while actually crippling one's judgement and leading to reckless errors.
Barbiturates and Pain Killers: Used to relieve anxiety or reduce pain. These drugs suppress mental alertness.
Cough Medicine: Cause central nervous system depression, reduced reaction time and high probability of overdose.
Motion Sickness Drugs: Cause drowsiness and depressed brain function, and temporary deterioration of judgement making skills.
Diuretics: Change the osmotic balance of the body.