2017 HCHB_digital

Drugs in Diving
DIVING – PRECAUTIONS FOR OTC MEDICINES USE
Any drug which acts on a physiological or psychological parameter of an individual
may well impact on diving and diving safety. If a person has a condition which
is a contraindication to diving, it is better not to dive than to take a medicine to
ameliorate the symptoms.
The following classes of drugs may be unsafe to use while
diving.
Analgesics
Analgesics may contain a combination of products including codeine or sedating
antihistamines such as doxylamine. These ingredients may cause drowsiness
or contribute to the deterioration in mental function associated with nitrogen
narcosis.
Bronchodilators
Theophylline may be associated with cardiac arrhythmias and central nervous
system effects such as anxiety and restlessness. Salbutamol is short-acting and
may stop working during diving. Diving should be avoided if a bronchodilator is
considered necessary.
Decongestants (short acting)
Short-acting decongestants such as phenylephrine may wear off during the
dive, and cause a reverse block. Although their use by divers is widespread,
decongestant use may encourage diving with underlying conditions that are
contraindicated, for example, upper respiratory tract infections or allergies.
Decongestants can cause tachycardia, and vertigo or disorientation have also been
reported during diving.
Ear wax softening drops
Although the use of ear wax softening drops is not contraindicated for diving, ear
wax should be removed before diving.
Nicotine/smoking
Nicotine increases production of carboxyhaemoglobin, which lowers the oxygencarrying
capacity of the blood, and causes an overall decrease in cardiovascular
fitness. The acute effect of nicotine is to increase heart rate and blood pressure.
Smoking also increases mucus production and reduces the ability for the lungs
to clear secretions, which could increase the risk of air trapping and pulmonary
barotrauma.
Recreational drugs
All recreational drugs such as alcohol, marijuana, cocaine, opiates, etc., are
strongly advised against when diving.
Sedating drugs
Antihistamines used for allergy or as an antiemetic could cause drowsiness
or contribute to the deterioration in mental function associated with nitrogen
narcosis.
Herbal remedies
Herbal remedies should be avoided in combination with diving, as many of these
are inadequately labelled as to their contents. Some “herbal” remedies have
been found to contain steroids, opiates and even Viagra.
Anyone intending to dive after having taken ANY kind of medicine should first
seek a medical opinion, preferably from a Dive Doctor.
REVIEWED BY Dr Chris Sames, Senior Medical Officer, Slark Hyperbaric
Unit, Waitemata DHB, March 2017.
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