Drink Driving and the ‘Mellanby Effect’

With every drink of alcohol you consume the blood alcohol level in your bloodstream increases.

You may not notice it, but there is a significant difference in the way the alcohol effects your behaviour and, how you feel, depending on whether you are still drinking and your blood alcohol level is increasing or whether you have stopped drinking and, particularly if it’s the next morning after a big night, your blood alcohol level is decreasing.

Some people know it as ‘acute tolerance’ and others know it as ‘the Mellanby effect’.  An Australian Consultant Forensic Physician described it as follows,

“Acute tolerance is the expression of central nervous system adaptation which occurs during the course of a single drinking episode and beyond (the Mellnby effect, Mellanby, 1920).  Acute tolerance means that the outward signs of drunkenness observed after a long period of drinking and afterwards, are much less obvious than those observed if the same breath alcohol concentration had been attained in a much shorter drinking period.  In effect, it means that at a given breath alcohol concentration, impairment"

When we are on holidays, most of us are in a state of mild euphoria because we are relaxed and with friends. This is a time when the influence of the Mellanby effect can be particularly important. If you have been drinking the night before and your blood alcohol level is decreasing, then you are less likely to feel a sense of impairment in your levels of coordination.

In fact, many drivers caught by random breath tests early in the morning are often amazed to find that they are over the limit. The combination of the Mellanby effect and a happy sense of euphoria associated with the freedom of being on holidays can trick even the best of us into believing that we are in a proper state to drive.

If you find yourself in a situation where you have been charged by the police for a drink driving offence, you should look to find experienced legal advice as quickly as possible.

Contact Mario Licha

Mario Licha has more than a decade’s experience handling matters for motorists charged with these and related offences. You can send him your details by clicking here or by calling: 0402 968 997

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