Dr Marcus Brauer & Associates is an occupational medicine, travel clinic and general practice, linked to Mediclinic and based at the V&A Waterfront in Cape Town.

Dr Brauer gives his advice on telling the difference between holiday food poisoning and getting a tummy bug… and what to do about it.

1. What are the general symptoms of food poisoning – when is it food poisoning and not a bug?

An upset stomach – or vomiting and diarrhoea as it’s often referred to – can be caused by chemicals or toxins, or by living organisms such as bacteria, viruses or parasites.

In general, if we speak about food poisoning, we’re referring to an upset stomach caused by chemicals or toxins. This typically occurs when food is a few days old and when it has not been refrigerated properly, or if it has been contaminated by toxin-producing bacteria. Foods that are particularly prone to this are fish, meat and starches.

The difference between food posioning and a ‘tummy bug’ is that food poisoning usually has a rapid start within hours after eating a contaminated meal and once the stomach has emptied itself, you usually start to feel better about 12 hours later.

If a bug makes you ill, it will first incubate in the body for a few days and then start to make you feel progressively worse – symptoms will usually last for at least 48 hours before you start to feel better. 

2. When you're travelling, what precautions can you take to avoid getting food poisoning?

It’s wise to remember the following advice: ‘Cook it, boil it, peel it or forget it …’.

This means:

  • Be wary of local, untreated tap water and only drink reputable bottled and sealed, boiled or properly chemically sterilised water. • Eat freshly prepared cooked meals. Vegetarian meals are usually safer options.
  • Eat at busy restaurants frequented by locals, as the food does not get a chance to stand around for long, and if the food was bad, the locals wouldn’t be eating there!
  • Be wary of raw foods like raw fish, salads and unpeeled fruit, as well as ice – living organisms can comfortably survive on (and in) these substances.
  • Always wash your hands before eating and after visiting the bathroom. Carrying a small container of alcohol-based waterless hand cleanser allows you to clean your hands without needing to use communal soap and towels, which may be laden with bugs if they’re not changed regularly. 

3. Many of us think we know how to deal with food poisoning with over-the-counter medications like Immodium or Buscopan in our first-aid kit. But when should you be concerned and seek medical intervention – is there anything to look for?

It’s acceptable to manage an episode of diarrhoea and vomiting yourself with Buscopan, which helps against cramps and an anti-nauseant such as Valoid. Immodium can slow down diarrhoea but beware as it can also potentially trap harmful bacteria in your body and do more harm than good. I would use Immodium with caution as a short-term control measure only and only if absolutely necessary in the context of long trips where access to toilets will be problematic.

Seek medical attention immediately if:

  • Vomiting and diarrhoea that lasts for more than two days or gets progressively worse.
  • Vomiting and diarrhoea in a young child under five years old is potentially very dangerous and should be monitored if symptoms persist for more than 24 hours or if there are any of the warning signs below.
  • Vomiting and diarrhoea in a pregnant woman.
  • Signs of lethargy and extreme tiredness, as well as prominent weakness or dizziness. • Inability to swallow and keep down water.
  • Any blood or mucous in the stools.
  • Fever of more than 38 degrees centigrade.
  • Any rash or severe headache associated with the vomiting and diarrhoea.
  • An abdominal upset after visiting a malaria area can be a sign of malaria and should be investigated. 

4. If you don't have access to drugs or doctors, are there any simple solutions you can use to alleviate your symptoms?


When you have an upset stomach, you should not challenge the stomach with lots of food. Your most important priority is not to dehydrate. You can always catch up on food later when you’re feeling better, but becoming dehydrated can have severe consequences.

Make up your own oral rehydration solution by mixing eight teaspoons of sugar and half a teaspoon of salt in one litre of boiled, cooled water.Now take regular small sips. You want to consume about one cup (250ml) for every vomit or loose stool to replace your losses. Aim to urinate at least four to six times per day, and your urine should be clear and pale. If it is dark and concentrated, you need to be drinking more.

Taking an anti-nauseant can help you keep fluid in and reduce the risk of dehydration. It’s important to rest, and take paracetamol if you have a fever. You may also want to consider nibbling on bland foods such as mashed bananas and grated apples. Marie biscuits and plain salted pretzels are another gentle snack for an upset stomach. 

5. As a rule of thumb, how long does your typical bout of food poisoning last and is there anything you need to do to prevent it recurring?

With food poisoning you should start to feel better after 12 hours, with a viral gastroenteritis you will start feeling better after 24 to 48 hours. With a bacterial or parasitic infection you will usually become worse, until you see a doctor and receive appropriate prescribed medicine. Food poisoning usually lasts less than 24 hours.

The prevention lies purely in avoiding food that is at risk of having been contaminated.

Disclaimer: The information provided in this article was correct at the time of publishing. At Mediclinic we endeavour to provide our patients and readers with accurate and reliable information, which is why we continually review and update our content. However, due to the dynamic nature of clinical information and medicine, some information may from time to time become outdated prior to revision.