Loperamide is an anti-diarrhoeal medicine that slows the gut. It is used for short-term relief of sudden diarrhoea and for managing ongoing diarrhoea in some long-term conditions. It is widely available as 2 mg tablets and a paediatric syrup. It controls the symptom without treating what caused it.
What is Loperamide?
Loperamide hydrochloride is Schedule 2 in South Africa — available from a pharmacist — and sold under many names:
| Product | Form |
|---|---|
| Adco-Loperamide, Cipla-Loperamide, Norimode, Gastron, Betaperamide | Tablet 2 mg |
| Adco-Loperamide | Syrup 1 mg/5 ml |
Being dispensed one rather than another is ordinary generic substitution.
Loperamide acts on opioid receptors in the wall of the gut. That sounds concerning, but the crucial detail is that loperamide is designed not to cross into the brain at normal doses — it is actively pumped back out by a transporter at the blood-brain barrier. At recommended amounts it has no pain-relieving or euphoric effect and works purely on the bowel.
Acting there, it:
- Slows the muscular contractions that move contents through the intestine.
- Allows more time for water and salts to be absorbed, so stools become firmer.
- Increases tone in the anal sphincter, which helps with urgency.
Loperamide is symptom control, not a cure. It does not kill bacteria, clear a virus or treat inflammation. It makes diarrhoea less frequent and less urgent while the underlying cause resolves — or while it goes untreated, which is exactly why it is inappropriate in some situations.
What is Loperamide commonly used for?
- Acute non-specific diarrhoea — the ordinary, sudden kind with a stomach upset.
- Traveller’s diarrhoea, for symptom control, often where reaching a bathroom is the practical problem.
- Chronic diarrhoea in diagnosed conditions, such as irritable bowel syndrome with diarrhoea, or inflammatory bowel disease in remission — under medical guidance.
- Diarrhoea after bowel surgery, or in people with a stoma, to reduce output.
- Diarrhoea caused by some treatments, where a doctor has advised it.
- Reducing urgency and frequency, often what people most need help with.
Rehydration matters more than stopping the diarrhoea. The real danger in diarrhoea is losing fluid and salts, particularly in children and older people. Oral rehydration solution addresses that; loperamide does not. If you do only one thing, replace fluids properly — do not let a tablet substitute for it.
Most acute diarrhoea settles on its own within a couple of days.
How Loperamide fits into this medicine category
| Group | Examples | What it does |
|---|---|---|
| Antimotility | Loperamide | Slows the gut; controls diarrhoea symptoms |
| Oral rehydration | ORS sachets | Replaces lost fluid and salts — the priority |
| Adsorbents | Kaolin, pectin (Pectrolyte) | Firm stool consistency; gentler |
| Antispasmodics | Hyoscine | Relieve cramping, not diarrhoea itself |
| Anti-nausea | Metoclopramide | Nausea and vomiting |
| Antibiotics | Ciprofloxacin, metronidazole | Only for specific proven infections |
Antibiotics are usually unnecessary for diarrhoea and occasionally harmful. See the digestive and stomach medicines hub.
What to check before using Loperamide
Do not take loperamide if you have a fever with bloody diarrhoea. This is the most important restriction. Those signs suggest an invasive bacterial infection, and slowing the gut keeps the organism and its toxins in the body longer — turning a manageable illness into a serious one.
Do not use it, or ask first, if you:
- Have blood or mucus in the stool.
- Have a high fever alongside diarrhoea.
- Have severe abdominal pain, or a swollen, tender abdomen.
- Have ulcerative colitis in a flare, or are at risk of toxic megacolon.
- Have had recent antibiotics. Diarrhoea afterwards may be C. difficile, where loperamide can be dangerous.
- Have liver disease, where loperamide can accumulate.
- Are constipated as well, or have not passed wind.
- Are pregnant or breastfeeding.
- Are giving it to a child. Loperamide is generally avoided in young children, where oral rehydration is the mainstay. Ask a pharmacist about age and weight first.
- Take medicines that affect heart rhythm, or that inhibit liver enzymes such as certain antifungals, HIV medicines or quinidine.
Do not exceed the stated maximum, and do not take it for more than 48 hours for sudden diarrhoea without medical advice.
Possible cautions and when to ask a pharmacist or doctor
Common effects are constipation, abdominal cramping, bloating, nausea, dry mouth and dizziness.
Stop and seek medical attention if you develop:
- A swollen, distended or very tender abdomen.
- No bowel movement at all combined with ongoing pain, which may indicate obstruction.
- Bloody stools or fever appearing after you started it.
- Severe constipation once the diarrhoea settles.
- Swelling of the face, lips or tongue, or difficulty breathing.
- A severe rash or blistering skin.
- Palpitations, fainting or an irregular heartbeat.
That last point deserves emphasis. Taken in large quantities, loperamide causes dangerous heart rhythm disturbances and cardiac arrest. Very high doses have been misused to self-treat opioid withdrawal or to produce a high — at such doses the blood-brain barrier transporter is overwhelmed, and the heart effects are severe. This has caused deaths. At recommended amounts the medicine is safe and does not reach the brain; deliberately exceeding them is genuinely life-threatening rather than simply ineffective. Anyone using it that way needs medical help, and that conversation is worth having.
Seek prompt advice for signs of dehydration — marked thirst, little or dark urine, dizziness on standing, dry mouth. In a child: drowsiness, sunken eyes, no wet nappies, or no tears when crying. Do not delay in a young child or an older person.
See a doctor if diarrhoea lasts more than two days, keeps returning, follows foreign travel, comes with unintended weight loss, or wakes you at night — these point to a cause that needs identifying rather than suppressing.
Related medicine guides
Frequently asked questions
What is loperamide used for? Short-term control of diarrhoea — reducing how often and how urgently you need the toilet. It is available from a pharmacist.
What are loperamide tablets used for? The 2 mg tablets are used for acute diarrhoea and, under medical guidance, for ongoing diarrhoea in some long-term conditions.
Does it cure diarrhoea? No. It controls the symptom while the cause settles. It has no effect on infection or inflammation.
How quickly does it work? Usually within a few hours of the first dose. Follow the pack instructions and do not exceed the maximum.
When should I not take it? With a fever and bloody diarrhoea, severe abdominal pain, or diarrhoea after recent antibiotics. Slowing the gut can make those worse.
Can I give it to my child? Ask a pharmacist first. It is generally avoided in young children, where oral rehydration solution is the priority.
Is loperamide addictive? At recommended doses it does not reach the brain and has no such effect. Taking large quantities is dangerous for the heart and has caused deaths.
Should I still drink extra fluids? Yes. Replacing lost fluid and salts matters more than stopping the diarrhoea — oral rehydration solution is better than water alone.