Explosive Diarrhoea: Causes, Treatment and When to See a GP

No-one wakes up in the morning planning to memorise where the nearest toilet is. Explosive diarrhoea is unexpected and can come as a shock — a sudden, urgent need to go, along with the other symptoms all at once.

As alarming as it sounds, explosive diarrhoea is something that happens to a lot of people. Usually it’s caused by a short-lived stomach infection that settles on its own. Even so, one of the most important things I do as a GP is work out whether it’s a self-limiting illness or something that needs closer attention.

This guide explains what explosive diarrhoea is, what usually causes it, the treatment options, and when professional advice is worth seeking.

Worried about your symptoms? Book online, or call and WhatsApp us on 07424 172034. This article is for general information and is not a substitute for personalised medical advice.

What Is Explosive Diarrhoea?

“Explosive diarrhoea” isn’t a formal medical term. It describes a diarrhoeal episode that is both sudden and very intense, and can be difficult to control.

Some people describe a loss of control — a sudden urge to go with little or no warning. Others describe passing very watery stools frequently over a short period, often with abdominal cramps or other symptoms.

Although it may be a brief episode, to a doctor it can point to several different things. That’s why your clinical history matters so much.

What Causes Explosive Diarrhoea?

One of the biggest misconceptions is that this always has a single cause. In reality there are many possible reasons, and the same symptom can have a completely different underlying nature from one person to the next.

The causes I come across most often include:

• Viral gastroenteritis
• Bacterial food poisoning
• Travellers’ infections
• Some medicines (particularly antibiotics)
• Lactose or gluten intolerance
• Irritable bowel syndrome (IBS)
• Inflammatory bowel disease (IBD), such as Crohn’s disease or ulcerative colitis
• Rarer causes, including parasitic infections such as Cyclospora

There has recently been news of Cyclospora outbreaks among travellers to certain countries. This infection can cause watery diarrhoea, but it’s quite rare in the UK and is usually linked to travel or contaminated imported food.

One thing I often tell my patients is not to jump to conclusions too quickly. Two people can have almost identical symptoms with very different causes — which is why consulting a GP is often more useful than trying to diagnose the problem online. Rather than working out the cause on your own, book a consultation with Dr Faizal: a proper assessment can identify what’s causing your symptoms and whether any tests or treatment are needed.

Common Symptoms of Explosive Diarrhoea

Watery or loose bowel movements are rarely the only symptom. Some people feel drained, tired or drowsy before an episode; others notice nothing but frequent trips to the bathroom.

Common symptoms include:

• Watery or loose bowel movements
• A sudden, urgent need to go to the toilet
• Abdominal pain or stomach cramps
• Bloating
• Nausea or vomiting
• Exhaustion and tiredness
• Loss of appetite
• Sometimes a fever

Dehydration is another symptom that shouldn’t be overlooked. When you lose a lot of fluid through loose stools, dehydration can develop surprisingly quickly — especially if you’re also vomiting or struggling to keep fluids down. Often it’s the dehydration, rather than the diarrhoea itself, that leaves you feeling so tired.

Common signs of dehydration include:

• Feeling thirsty
• Passing only small amounts of urine, or dark urine
• Dizziness when standing up
• A dry mouth
• Feeling unusually tired

Young children, older people and those with other medical conditions can become dehydrated faster. If your child has stopped drinking enough, seems unusually drowsy, or isn’t passing urine, seeing a GP promptly is the right move.

When Should You See a GP?

Two questions I hear a lot are: “Should I wait a couple of days?” and “Will it go away?”

In most cases, it’s reasonable to wait a little. Most stomach infections settle within a few days, and the body has natural defences that help clear them. But if symptoms aren’t improving, or you develop signs of dehydration, you should see a GP.

See a GP if you have any of the following:

• Diarrhoea lasting more than 7 days
• Repeated episodes of diarrhoea
• Blood in your stools
• Significant stomach pain
• Vomiting that won’t settle
• A fever that doesn’t resolve
• Signs of dehydration
• Recent travel abroad before becoming unwell
• Recent antibiotic use
• Unexplained weight loss

How Can a GP Help?

Many people assume seeing a GP means lots of laboratory and imaging tests. Sometimes those are essential, but usually they aren’t the first step. The most valuable part of the consultation is listening to your story — the timing, progression and likely triggers of your symptoms often tell me more than any single test.

I’ll ask about the duration and nature of your symptoms, whether family or friends have had the same, your diet, and your travel and medication history. Sometimes that’s enough to make a diagnosis on the spot: if your symptoms fit a viral infection, you may not need any tests at all, and the advice is simply about hydration and rest.

But if your symptoms don’t fit that pattern, I may recommend further tests, such as:

• Blood tests
• Stool testing to look for infection
• Testing for conditions such as coeliac disease
• Further investigation of the bowel if symptoms are ongoing and unexplained

How Is Explosive Diarrhoea Treated?

It depends on the cause. First and foremost, replace lost fluids and salts by drinking enough water, or using an oral rehydration solution if needed. You can eat if you feel up to it.

A question I hear often is whether antibiotics or anti-diarrhoea medicines are needed. The simple answer is usually no. Explosive diarrhoea is caused by viruses most of the time, and antibiotics don’t treat viruses — worse, unnecessary antibiotics can upset the balance of bacteria in your gut. Anti-diarrhoea medicines can be similarly unhelpful, because you generally want to clear the infection rather than suppress it.

How Long Does Explosive Diarrhoea Last?

This is one of the first questions in almost every consultation. The honest answer is that it depends on the cause.

For a viral infection, symptoms usually start to ease within 2–3 days and clear within about a week. Some cases of food poisoning also settle within a week, though others take a little longer.

If explosive diarrhoea lasts more than a week, or keeps coming back, it’s better to book an appointment with a GP than to keep waiting. Some people find their stomach stays sensitive for a while after recovering — that’s normal and usually settles over a few weeks.

Can You Prevent Explosive Diarrhoea?

Not entirely — but some simple measures reduce the risk of the infections that cause it. Washing your hands regularly is one of the easiest and most effective, particularly after using the bathroom and before preparing or eating food, as it limits the spread of bacteria and viruses.

When travelling abroad, especially where food hygiene standards may be lower, it’s worth being more cautious: drink bottled or purified water, avoid undercooked food and wash fruit. There’s recently been media coverage of Cyclospora infections linked to travel and contaminated food. The risk in the UK is low, but it’s worth telling your GP about recent travel if you have prolonged diarrhoea.

Frequently Asked Questions

What causes explosive diarrhoea?

Explosive diarrhoea can have many causes — most often a viral infection, bacterial gastroenteritis or food poisoning. Less common causes include certain medicines, food intolerance, inflammatory bowel disease, or a parasitic infection such as Cyclospora.

How do you stop explosive diarrhoea?

First, replace the fluids and salts you’re losing by drinking plenty of water or an oral rehydration solution. Most viral infections settle on their own. See a GP if symptoms are severe or persistent, or you show signs of dehydration.

How long does explosive diarrhoea usually last?

For most people, recovery begins within 2–3 days and settles within about a week. If your symptoms don’t improve after that, keep returning, or get worse, you should consult a GP.

Should I take antibiotics?

Usually no. Most cases are caused by viruses, which antibiotics don’t treat, and unnecessary antibiotics can upset the balance of bacteria in your gut. They’re only used where there’s evidence of a specific infection that needs them.

When should I be concerned about diarrhoea?

See a GP if you have blood in your stools, severe abdominal pain, a fever that won’t settle, signs of dehydration, or diarrhoea lasting more than a week.

Related Services

If your symptoms are persistent or need further investigation, Dr Faizal can arrange the right tests and advise on the appropriate care. These services may also be useful:

• Private GP Appointment — a consultation to assess your symptoms and history, order any tests, and decide on next steps.
• Private Blood Tests — to help identify an underlying cause such as infection, inflammation or a nutritional problem.
• Coeliac Disease Blood Test — where symptoms are persistent or point towards gluten intolerance.
• Liver Function Test — where liver blood tests may help explain gastrointestinal symptoms.
• Specialist Referrals — onward referral where further investigation is needed.