It’s the captain’s cocktail and you stay on late chatting to the first officer about the ship’s engines.  Then you adjourn to the bar to continue the conversation.

Next morning, even though the seas are calm, you feel distinctly nauseous and head for the sick bay. But here’s the thing:  you don’t tell the ship’s doctor you might be the worse for wear.  Instead, you blame the rocking ship and get recorded as a case of mal de mer.

Now a cruise ship medical expert has revealed the secrets patients weren’t telling doctors in his latest book, claiming many passengers try and mask their hangovers as sea sickness.

In Ben Mcfarlane’s new book, Cruise Ship SOS, he shares with readers what a medical colleague told him. “Seasickness is a very convenient illness.”

“You’ll notice that the people who suffer the most are the ones who were at the bar knocking back mojitos at 2am the previous night. ”

His colleague also said, “You’ll also see that these people never have hangovers. They come to us with sore heads in the morning because they’re prone to ‘migraines.’”

“They feel sick when they wake up because of the air-conditioning in the staterooms, not because of all the vintage port they consumed at midnight.”

The book also reveals the medical staff took revenge on hangover sufferers who were faking seasickness. They would provide cures like fried garlic and pork, saying these were “the stuff of maritime legend. A time-honoured cure for seasickness.”

So just be careful the next time you’re on your cruise and the doctor suggest this unusual remedy – you’ll know what it means.

Here are some REAL remedies to prevent a hangover:

1. Avoid drinks high in congeners

Ethanol is the main ingredient in alcoholic drinks but booze also contains varying amounts of congeners. Congeners are toxic chemicals that include methanol, isopenthanol and acetone. Drinks which are high in congeners seem to increase the frequency and intensity of hangovers. Drinks high in congeners include whisky, cognac and tequila. And avoid the bourbon whisky – that’s especially high in congeners. Colourless drinks like vodka, gin and rum have low levels of congeners.

2. Hair of the dog does work

There is some science behind having a drink when you’re hung over. After drinking, your body converts methanol into formaldehyde and this is the highly toxic. And it’s also partly the substance that is responsible for hangover symptoms. But consuming alcohol the morning after drinking heavily can inhibit this conversion process, preventing formaldehyde from forming. But while it might be a temporary remedy, it most likely just delays the inevitable hangover.

3. Drink plenty of water before you go to bed

Alcohol can contribute to dehydration and is one of the causes of hangovers. Just make sure you have a glass of water in between drinks or at least have some H2O before you go to bed to help stave away that hangover.

4. Have a good breakfast in the morning

Hangovers are sometimes associated with low levels of blood sugar, something known as hypoglycaemia. While it might not be the major cause of hangovers, it may contribute to symptoms like weakness and headaches. So having a good breakfast in the morning or a late night meal may help maintain your blood sugar levels.