Acidex Advance Oral Suspension Peppermint Flavour 200mg/1000mg – 500ml
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What Is Acidex Advance Oral Suspension Peppermint Flavour 500ml Used For?
For those who manage heartburn, acid reflux, and indigestion regularly, having a reliable supply of an effective preparation at home makes a real difference to daily comfort and routine. Acidex Advance Oral Suspension Peppermint Flavour 500ml is the economy-sized format of the popular peppermint variant, offering the same proven alginate-based raft-forming formula in a larger bottle for those who use the product frequently or wish to avoid the inconvenience of running out. Like its smaller counterpart, it is designed to help relieve the symptoms of gastro-oesophageal reflux, including heartburn, acid regurgitation, and indigestion after meals and during the night.
The formulation works through a combination of physical raft formation and direct antacid activity. Sodium alginate, when taken after a meal, reacts with stomach acid to produce a thick, cohesive gel that floats on the surface of the stomach contents, forming a buoyant raft that helps to physically prevent acid from refluxing upward into the oesophagus. Sodium bicarbonate contributes the carbon dioxide needed to make this raft float effectively and also directly neutralises excess stomach acid. Calcium carbonate provides additional acid-neutralising activity and helps to reinforce the raft structure. Together, these three active ingredients work in concert to address the mechanical cause of reflux and the chemical irritation it produces, providing effective and sustained symptomatic relief.
The peppermint flavour gives this preparation a cool, refreshing taste that many people find particularly pleasant when experiencing the discomfort of heartburn. The 500ml bottle is identical in formulation to the 250ml peppermint variant and is simply a more economical option for regular users. All standard dosing, usage, and storage guidelines apply, including the important requirement to discard the bottle 28 days after opening regardless of remaining volume. The suspension must be shaken thoroughly before every dose and measured accurately using a 5ml medicine spoon or oral dosing syringe.
Acidex Advance is suitable for adults and young people aged 12 and over. Those on sodium-restricted diets, with kidney impairment, or taking other regular medicines should seek pharmacist advice before using this product. If your symptoms are severe, persistent beyond one week, or accompanied by difficulty swallowing, unexplained weight loss, or vomiting, please see your GP rather than continuing to self-treat. A Pearl Chemist Group pharmacist can provide guidance on whether this is the right product for your symptoms, and you can also explore our full heartburn and indigestion range.
How to Use Acidex Advance Oral Suspension Peppermint Flavour 500ml
- Shake thoroughly before every dose. Active ingredients settle with time. Always shake the bottle well before measuring to ensure an accurate and consistent dose.
- Measure accurately. Use a calibrated 5ml medicine spoon or oral dosing syringe. Do not use a household teaspoon.
- Take after meals and at bedtime. The alginate raft forms most effectively on top of stomach contents. Always take after eating rather than on an empty stomach.
- Swallow directly without diluting. Do not mix with water or other drinks before taking, as this may reduce the effectiveness of the raft-forming process.
- Remain upright after post-meal doses where possible. Staying upright for 20 to 30 minutes supports optimal raft positioning. The bedtime dose may be taken before lying down.
- Replace the cap and record the opening date. Write the date of opening on the label immediately and store below 25°C.
Important note for the 500ml pack
- Despite the larger volume, this bottle must be discarded 28 days after opening. Write the opening date on the label as a reminder. If the full 500ml is unlikely to be used within 28 days by the same household, consider the 250ml size to avoid waste.
- Take other medicines at least 2 hours before or after each dose of Acidex Advance to minimise the risk of interaction.
Acidex Advance Oral Suspension Peppermint Flavour 500ml Side Effects
Generally well tolerated when used as directed. Side effects are uncommon.
Common side effects (may affect more than 1 in 10 people)
- Increased wind or bloating from carbon dioxide released during raft formation — normal, mild, and temporary
Less common side effects (may affect between 1 in 10 and 1 in 100 people)
- Nausea or unpleasant taste, particularly with larger doses
- Constipation related to calcium carbonate
- Diarrhoea in some individuals
- Mild stomach discomfort or cramping
Rare side effects (may affect fewer than 1 in 100 people)
- Allergic reaction to ingredients including parabens or peppermint flavouring, presenting as rash, itching, or swelling
Stop using and seek medical help if you experience:
- A serious allergic reaction including facial or throat swelling, difficulty breathing, or a widespread rash — call 999 immediately
- Severe or worsening abdominal pain
- Any symptom you believe may be related to this product
Report any unexpected reaction via the MHRA Yellow Card scheme at yellowcard.mhra.gov.uk or speak to your Pearl Chemist Group pharmacist.
How to Store Acidex Advance Oral Suspension Peppermint Flavour 500ml
- Temperature: Store below 25°C. Keep away from direct sunlight and heat sources.
- Do not refrigerate.
- After opening: Discard 28 days after first opening regardless of remaining volume. Write the opening date on the label immediately.
- Before each use: Shake well before measuring each dose.
- Cap: Replace firmly after every use.
- Children: Keep out of the sight and reach of children at all times.
- Expiry: Do not use after the expiry date on the bottle and outer packaging.
- Disposal: Ask your Pearl Chemist Group pharmacist about safe disposal of medicines you no longer need.
Who Is Acidex Advance Oral Suspension Peppermint Flavour 500ml Suitable For?
Acidex Advance Oral Suspension Peppermint Flavour 500ml is suitable for adults and young people aged 12 and over experiencing symptoms of gastro-oesophageal reflux who prefer a peppermint-flavoured liquid antacid and require or prefer an economy-sized pack for regular or household use.
Suitable for:
- Adults aged 18 and over experiencing heartburn, acid reflux, or indigestion after meals or at night
- Young people aged 12 to 17, subject to appropriate adult supervision
- Those who use the product regularly and benefit from a larger economy pack size
- Households where more than one person uses the product
- Those who prefer a peppermint flavour and a liquid suspension format
- People who find alginate raft-forming preparations more effective than simple antacids for their reflux symptoms
- Pregnant women experiencing heartburn, subject to GP or midwife guidance on sodium content
Not suitable for:
- Children under 6 years of age
- Children aged 6 to 11 years unless specifically directed by a doctor
- Anyone with a known allergy or hypersensitivity to any ingredient including parabens or peppermint flavouring
- Those with a known sensitivity to peppermint or menthol-containing preparations
Use with caution or seek advice first if you:
- Are on a sodium-restricted diet
- Have impaired kidney function
- Are taking any prescribed or over-the-counter medicines
- Are pregnant or breastfeeding
- Have severe, persistent, or worsening symptoms, or symptoms accompanied by difficulty swallowing, weight loss, or vomiting
Speak to a Pearl Chemist Group pharmacist for free, personalised guidance on suitability.
Active Ingredients in Acidex Advance Oral Suspension Peppermint Flavour 500ml
| Ingredient | Strength per 5ml dose | Role |
|---|---|---|
| Sodium alginate | 200mg | Primary raft-forming active ingredient derived from brown seaweed. Reacts with stomach acid to form a thick, buoyant gel raft on the surface of the stomach contents, physically preventing acid from refluxing into the oesophagus. |
| Sodium bicarbonate | 133.5mg | Generates carbon dioxide that makes the alginate raft buoyant so it floats on stomach contents. Provides mild direct antacid activity by neutralising excess stomach acid. |
| Calcium carbonate | 80mg | Provides additional antacid activity by directly neutralising excess stomach acid. Also helps to strengthen and stabilise the alginate raft structure. |
Acidex Advance Oral Suspension Peppermint Flavour 500ml Dosage — How Much to Take
Adults and young people aged 12 and over
- Dose: 10–20ml (2 to 4 x 5ml spoonfuls) per dose.
- When to take: After meals and at bedtime.
- Maximum daily dose: 4 doses in any 24-hour period (maximum 80ml per day).
- How to take: Shake well before use. Measure with a calibrated 5ml medicine spoon or oral syringe. Take orally after food.
Children aged 6 to 11 years
5–10ml after meals and at bedtime, under medical supervision only.
Children under 6 years
Not recommended.
Elderly patients
Standard adult dosage applies. Use with caution if kidney function is impaired — consult pharmacist or GP first.
Important dosage notes
- Do not exceed 4 doses in 24 hours.
- Shake the bottle well before every dose.
- Do not use continuously for more than 7 days without pharmacist or GP guidance.
- Discard 28 days after opening regardless of remaining volume in the 500ml bottle.
Precautions When Using Acidex Advance Oral Suspension Peppermint Flavour 500ml
Before you use this product
- Check the expiry date and that the bottle seal is intact before first use.
- Review drug interactions and consult your pharmacist if you take any regular medicines.
- If you have a known sensitivity to peppermint or menthol, use the aniseed flavour variant instead.
- If on a sodium-restricted diet or with kidney disease, seek pharmacist or GP advice before use.
During use
- Shake well before every dose.
- Measure accurately with a 5ml spoon or oral syringe.
- Do not mix with other drinks before taking.
- Take other medicines at least 2 hours apart from each dose.
- Do not exceed 4 doses in 24 hours.
Duration of use and the 500ml pack
- Do not use for more than 7 days continuously without pharmacist or GP guidance.
- Discard 28 days after opening regardless of remaining volume. Write the opening date on the label immediately.
Lifestyle considerations
- Avoid large evening meals and eating close to bedtime.
- Reduce alcohol, caffeine, and foods known to trigger your symptoms.
- Consider elevating the head of your bed to help with nocturnal symptoms.
When to seek medical advice
- Symptoms persist after 7 days of treatment.
- You experience difficulty swallowing, unexplained weight loss, or vomiting.
- Symptoms are severe or significantly affecting your daily life.
Our Pearl Chemist Group pharmacists offer free consultations and can advise on whether a GP referral is appropriate for your symptoms.
Full Ingredients in Acidex Advance Oral Suspension Peppermint Flavour 500ml
Active ingredients per 5ml dose: sodium alginate 200mg, sodium bicarbonate 133.5mg, calcium carbonate 80mg.
Excipients (inactive ingredients)
- Carbomer — thickening and suspending agent maintaining consistent viscosity and even distribution of active ingredients
- Methyl parahydroxybenzoate (E218) — preservative preventing microbial growth after opening
- Propyl parahydroxybenzoate (E216) — second preservative providing broad-spectrum antimicrobial protection; those with known paraben sensitivity should note its presence
- Sodium saccharin — artificial sweetener providing palatability without adding sugar
- Peppermint flavour — provides the characteristic cool, fresh peppermint taste of this variant
- Purified water — aqueous base of the suspension
If you have a known allergy to parabens (E216 or E218), peppermint, or any other listed ingredient, do not use this product. Speak to a Pearl Chemist Group pharmacist for an alternative, such as the aniseed flavour variant.
Last reviewed: May 2026.
Always read the patient information leaflet before use. A copy is included in the pack. For advice, speak to a Pearl Chemist pharmacist or call +44 (0)20 8672 2157.
What Is Acidex Advance Oral Suspension Peppermint Flavour 500ml Used For?
For those who manage heartburn, acid reflux, and indigestion regularly, having a reliable supply of an effective preparation at home makes a real difference to daily comfort and routine. Acidex Advance Oral Suspension Peppermint Flavour 500ml is the economy-sized format of the popular peppermint variant, offering the same proven alginate-based raft-forming formula in a larger bottle for those who use the product frequently or wish to avoid the inconvenience of running out. Like its smaller counterpart, it is designed to help relieve the symptoms of gastro-oesophageal reflux, including heartburn, acid regurgitation, and indigestion after meals and during the night.
The formulation works through a combination of physical raft formation and direct antacid activity. Sodium alginate, when taken after a meal, reacts with stomach acid to produce a thick, cohesive gel that floats on the surface of the stomach contents, forming a buoyant raft that helps to physically prevent acid from refluxing upward into the oesophagus. Sodium bicarbonate contributes the carbon dioxide needed to make this raft float effectively and also directly neutralises excess stomach acid. Calcium carbonate provides additional acid-neutralising activity and helps to reinforce the raft structure. Together, these three active ingredients work in concert to address the mechanical cause of reflux and the chemical irritation it produces, providing effective and sustained symptomatic relief.
The peppermint flavour gives this preparation a cool, refreshing taste that many people find particularly pleasant when experiencing the discomfort of heartburn. The 500ml bottle is identical in formulation to the 250ml peppermint variant and is simply a more economical option for regular users. All standard dosing, usage, and storage guidelines apply, including the important requirement to discard the bottle 28 days after opening regardless of remaining volume. The suspension must be shaken thoroughly before every dose and measured accurately using a 5ml medicine spoon or oral dosing syringe.
Acidex Advance is suitable for adults and young people aged 12 and over. Those on sodium-restricted diets, with kidney impairment, or taking other regular medicines should seek pharmacist advice before using this product. If your symptoms are severe, persistent beyond one week, or accompanied by difficulty swallowing, unexplained weight loss, or vomiting, please see your GP rather than continuing to self-treat. A Pearl Chemist Group pharmacist can provide guidance on whether this is the right product for your symptoms, and you can also explore our full heartburn and indigestion range.
How to Use Acidex Advance Oral Suspension Peppermint Flavour 500ml
- Shake thoroughly before every dose. Active ingredients settle with time. Always shake the bottle well before measuring to ensure an accurate and consistent dose.
- Measure accurately. Use a calibrated 5ml medicine spoon or oral dosing syringe. Do not use a household teaspoon.
- Take after meals and at bedtime. The alginate raft forms most effectively on top of stomach contents. Always take after eating rather than on an empty stomach.
- Swallow directly without diluting. Do not mix with water or other drinks before taking, as this may reduce the effectiveness of the raft-forming process.
- Remain upright after post-meal doses where possible. Staying upright for 20 to 30 minutes supports optimal raft positioning. The bedtime dose may be taken before lying down.
- Replace the cap and record the opening date. Write the date of opening on the label immediately and store below 25°C.
Important note for the 500ml pack
- Despite the larger volume, this bottle must be discarded 28 days after opening. Write the opening date on the label as a reminder. If the full 500ml is unlikely to be used within 28 days by the same household, consider the 250ml size to avoid waste.
- Take other medicines at least 2 hours before or after each dose of Acidex Advance to minimise the risk of interaction.
Acidex Advance Oral Suspension Peppermint Flavour 500ml Side Effects
Generally well tolerated when used as directed. Side effects are uncommon.
Common side effects (may affect more than 1 in 10 people)
- Increased wind or bloating from carbon dioxide released during raft formation — normal, mild, and temporary
Less common side effects (may affect between 1 in 10 and 1 in 100 people)
- Nausea or unpleasant taste, particularly with larger doses
- Constipation related to calcium carbonate
- Diarrhoea in some individuals
- Mild stomach discomfort or cramping
Rare side effects (may affect fewer than 1 in 100 people)
- Allergic reaction to ingredients including parabens or peppermint flavouring, presenting as rash, itching, or swelling
Stop using and seek medical help if you experience:
- A serious allergic reaction including facial or throat swelling, difficulty breathing, or a widespread rash — call 999 immediately
- Severe or worsening abdominal pain
- Any symptom you believe may be related to this product
Report any unexpected reaction via the MHRA Yellow Card scheme at yellowcard.mhra.gov.uk or speak to your Pearl Chemist Group pharmacist.
How to Store Acidex Advance Oral Suspension Peppermint Flavour 500ml
- Temperature: Store below 25°C. Keep away from direct sunlight and heat sources.
- Do not refrigerate.
- After opening: Discard 28 days after first opening regardless of remaining volume. Write the opening date on the label immediately.
- Before each use: Shake well before measuring each dose.
- Cap: Replace firmly after every use.
- Children: Keep out of the sight and reach of children at all times.
- Expiry: Do not use after the expiry date on the bottle and outer packaging.
- Disposal: Ask your Pearl Chemist Group pharmacist about safe disposal of medicines you no longer need.
Who Is Acidex Advance Oral Suspension Peppermint Flavour 500ml Suitable For?
Acidex Advance Oral Suspension Peppermint Flavour 500ml is suitable for adults and young people aged 12 and over experiencing symptoms of gastro-oesophageal reflux who prefer a peppermint-flavoured liquid antacid and require or prefer an economy-sized pack for regular or household use.
Suitable for:
- Adults aged 18 and over experiencing heartburn, acid reflux, or indigestion after meals or at night
- Young people aged 12 to 17, subject to appropriate adult supervision
- Those who use the product regularly and benefit from a larger economy pack size
- Households where more than one person uses the product
- Those who prefer a peppermint flavour and a liquid suspension format
- People who find alginate raft-forming preparations more effective than simple antacids for their reflux symptoms
- Pregnant women experiencing heartburn, subject to GP or midwife guidance on sodium content
Not suitable for:
- Children under 6 years of age
- Children aged 6 to 11 years unless specifically directed by a doctor
- Anyone with a known allergy or hypersensitivity to any ingredient including parabens or peppermint flavouring
- Those with a known sensitivity to peppermint or menthol-containing preparations
Use with caution or seek advice first if you:
- Are on a sodium-restricted diet
- Have impaired kidney function
- Are taking any prescribed or over-the-counter medicines
- Are pregnant or breastfeeding
- Have severe, persistent, or worsening symptoms, or symptoms accompanied by difficulty swallowing, weight loss, or vomiting
Speak to a Pearl Chemist Group pharmacist for free, personalised guidance on suitability.
Active Ingredients in Acidex Advance Oral Suspension Peppermint Flavour 500ml
| Ingredient | Strength per 5ml dose | Role |
|---|---|---|
| Sodium alginate | 200mg | Primary raft-forming active ingredient derived from brown seaweed. Reacts with stomach acid to form a thick, buoyant gel raft on the surface of the stomach contents, physically preventing acid from refluxing into the oesophagus. |
| Sodium bicarbonate | 133.5mg | Generates carbon dioxide that makes the alginate raft buoyant so it floats on stomach contents. Provides mild direct antacid activity by neutralising excess stomach acid. |
| Calcium carbonate | 80mg | Provides additional antacid activity by directly neutralising excess stomach acid. Also helps to strengthen and stabilise the alginate raft structure. |
Acidex Advance Oral Suspension Peppermint Flavour 500ml Dosage — How Much to Take
Adults and young people aged 12 and over
- Dose: 10–20ml (2 to 4 x 5ml spoonfuls) per dose.
- When to take: After meals and at bedtime.
- Maximum daily dose: 4 doses in any 24-hour period (maximum 80ml per day).
- How to take: Shake well before use. Measure with a calibrated 5ml medicine spoon or oral syringe. Take orally after food.
Children aged 6 to 11 years
5–10ml after meals and at bedtime, under medical supervision only.
Children under 6 years
Not recommended.
Elderly patients
Standard adult dosage applies. Use with caution if kidney function is impaired — consult pharmacist or GP first.
Important dosage notes
- Do not exceed 4 doses in 24 hours.
- Shake the bottle well before every dose.
- Do not use continuously for more than 7 days without pharmacist or GP guidance.
- Discard 28 days after opening regardless of remaining volume in the 500ml bottle.
Precautions When Using Acidex Advance Oral Suspension Peppermint Flavour 500ml
Before you use this product
- Check the expiry date and that the bottle seal is intact before first use.
- Review drug interactions and consult your pharmacist if you take any regular medicines.
- If you have a known sensitivity to peppermint or menthol, use the aniseed flavour variant instead.
- If on a sodium-restricted diet or with kidney disease, seek pharmacist or GP advice before use.
During use
- Shake well before every dose.
- Measure accurately with a 5ml spoon or oral syringe.
- Do not mix with other drinks before taking.
- Take other medicines at least 2 hours apart from each dose.
- Do not exceed 4 doses in 24 hours.
Duration of use and the 500ml pack
- Do not use for more than 7 days continuously without pharmacist or GP guidance.
- Discard 28 days after opening regardless of remaining volume. Write the opening date on the label immediately.
Lifestyle considerations
- Avoid large evening meals and eating close to bedtime.
- Reduce alcohol, caffeine, and foods known to trigger your symptoms.
- Consider elevating the head of your bed to help with nocturnal symptoms.
When to seek medical advice
- Symptoms persist after 7 days of treatment.
- You experience difficulty swallowing, unexplained weight loss, or vomiting.
- Symptoms are severe or significantly affecting your daily life.
Our Pearl Chemist Group pharmacists offer free consultations and can advise on whether a GP referral is appropriate for your symptoms.
Full Ingredients in Acidex Advance Oral Suspension Peppermint Flavour 500ml
Active ingredients per 5ml dose: sodium alginate 200mg, sodium bicarbonate 133.5mg, calcium carbonate 80mg.
Excipients (inactive ingredients)
- Carbomer — thickening and suspending agent maintaining consistent viscosity and even distribution of active ingredients
- Methyl parahydroxybenzoate (E218) — preservative preventing microbial growth after opening
- Propyl parahydroxybenzoate (E216) — second preservative providing broad-spectrum antimicrobial protection; those with known paraben sensitivity should note its presence
- Sodium saccharin — artificial sweetener providing palatability without adding sugar
- Peppermint flavour — provides the characteristic cool, fresh peppermint taste of this variant
- Purified water — aqueous base of the suspension
If you have a known allergy to parabens (E216 or E218), peppermint, or any other listed ingredient, do not use this product. Speak to a Pearl Chemist Group pharmacist for an alternative, such as the aniseed flavour variant.
Last reviewed: May 2026.
Always read the patient information leaflet before use. A copy is included in the pack. For advice, speak to a Pearl Chemist pharmacist or call +44 (0)20 8672 2157.
FAQs
Is the 500ml peppermint bottle the same as the 250ml version?
Yes. Acidex Advance Oral Suspension Peppermint Flavour 500ml contains exactly the same formulation as the 250ml peppermint variant — identical active ingredients at the same strengths per 5ml dose and the same excipients. The 500ml size is purely an economy format offering better value per millilitre for those who use the product regularly or who prefer to keep a larger supply at home.
Do I really need to discard the 500ml bottle after 28 days even if most of it is left?
Yes. Regardless of how much product remains, the bottle should be discarded 28 days after first opening. The preservative system in the suspension is designed to keep it safe for 28 days after the seal is broken. After this point, there is an increased risk of microbial contamination even if the product looks and smells unchanged. If you are unlikely to use a full 500ml within 28 days, the 250ml size may be a more practical choice to avoid waste.
Can I use this product if I am sensitive to strong flavours or have a sensitive stomach?
The peppermint flavour in Acidex Advance is derived from a flavouring agent and is generally well tolerated. However, if you have a known sensitivity to peppermint or menthol, or if you find minty flavours irritate your stomach, you should choose the aniseed flavour variant instead. If you have any concerns about tolerability, speak to a Pearl Chemist Group pharmacist before use.
How does Acidex Advance work for nocturnal heartburn?
The bedtime dose of Acidex Advance is specifically recommended to help manage overnight and early morning reflux symptoms. When taken before lying down, the alginate raft forms on the stomach contents and remains in position even when you adopt a horizontal posture, helping to reduce the acid reflux that can disturb sleep or cause discomfort in the early hours. Elevating the head of your bed by a few inches can further help to reduce nocturnal symptoms alongside the bedtime dose.
Is this product suitable for long-term use?
Acidex Advance is intended for short-term and as-needed relief of reflux symptoms. We recommend not using it continuously for more than 7 days without consulting your GP or pharmacist. If you find yourself needing regular daily treatment over an extended period, this is a sign that your reflux may warrant a formal medical assessment. Conditions such as gastro-oesophageal reflux disease (GORD) often respond well to specific prescribed treatments that address the underlying cause more effectively than over-the-counter preparations alone.
Can children use Acidex Advance Peppermint 500ml?
Acidex Advance is not recommended for children under 6 years of age. For children aged 6 to 11, use should only be under direct medical supervision. Young people aged 12 and over may use the product under adult supervision following the standard adult dosing guidelines. Reflux symptoms in children should always be assessed by a GP to identify the underlying cause and ensure the most appropriate management approach is taken.
What lifestyle changes can I make alongside taking Acidex Advance?
A number of lifestyle measures can help to reduce the frequency and severity of heartburn and acid reflux alongside using Acidex Advance. These include avoiding large meals, particularly in the evening, reducing alcohol and caffeine consumption, cutting back on fatty, spicy, and acidic foods, not eating within 2 to 3 hours of going to bed, elevating the head of your bed slightly, and maintaining a healthy weight, as excess weight around the abdomen can increase pressure on the stomach and worsen reflux. Our pharmacists at Pearl Chemist Group can provide personalised lifestyle advice alongside your treatment.