Instaraft Tablet 10s

Instaraft Tablet 10s is a three-component antireflux and antacid combination used to relieve heartburn, acid reflux, and symptoms of gastro-oesophageal reflux disease (GERD). Sodium alginate forms a physical gel raft that floats on stomach contents, preventing them from reaching the oesophagus. Sodium bicarbonate reacts with stomach acid to release carbon dioxide, which aerates the alginate gel into a buoyant raft. Calcium carbonate provides additional acid-neutralising activity and supplies calcium ions, which are critical for alginate gelation.

Instaraft Tablet 10s is a non-systemic antireflux formulation that works primarily through a physical raft-forming mechanism, rather than suppressing acid secretion. Each component contributes a precise role in raft formation and acid neutralisation.

Sodium alginate is a polysaccharide extracted from brown seaweed. On contact with stomach acid, alginate chains undergo pH-dependent gelation. Sodium bicarbonate reacts with hydrochloric acid (HCl) in the stomach, releasing carbon dioxide bubbles that become entrapped within the forming gel, converting the dense alginate gel into a buoyant, low-density foam raft that floats on gastric contents.

Calcium carbonate balances excess acid in the stomach and releases calcium ions, which connect alginate chains and support the raft. The resulting raft acts as a physical barrier at the gastro-oesophageal junction, removing acidic backwash and reducing the volume and acidity of material reaching the oesophagus.

This medicine doesn’t suppress acid secretion & is not a substitute for long-term GERD management or treatment of oesophagitis.

Heartburn and acid indigestion

Rapid acid neutralisation and raft formation provide fast symptomatic relief.

Gastro-oesophageal reflux disease (GERD)

Reduces frequency and severity of acid reflux episodes.

Reflux in pregnancy

Often prescribed by doctors to manage reflux during pregnancy.

Post-meal dyspepsia (indigestion)

Resolves regurgitation (contents from the stomach return up to the oesophagus), bloating, and discomfort after eating.

• Minimal drug absorption, which results in very few systemic side effects.

• The alginate raft physically moves acidic gastric contents away from the oesophageal junction.

• Raft forms within minutes of ingestion, providing quick symptomatic relief.

• Sodium bicarbonate increases the gastric PH rapidly by neutralising acid immediately.

• Calcium carbonate provides long-lasting acid-buffering (gastric acid neutralisation) and structurally supports the alginate raft.

• It does not interfere with normal acid secretion required for normal digestion.

Common side effects:

• Bloating and flatulence

• Belching

• Mild constipation

Uncommon side effects:

• Nausea

• Hypercalcaemia (high calcium levels in blood) with prolonged high-dose use

• Mild metabolic alkalosis (buildup of excess base or alkali in the body) with excessive sodium bicarbonate intake

Serious side effects requiring immediate attention:

• Systemic alkalosis, which may present as confusion, muscle cramps or tetany (involuntary muscle contractions), especially in patients with renal impairment

• Severe hypercalcaemia (extremely high levels of calcium), which may present as confusion, extreme weakness, abdominal pain or renal complications

• Milk-alkali syndrome (a triad of high calcium levels, metabolic alkalosis, & acute kidney injury) with excessive use of medication, along with high calcium dietary intake

Available as oral suspension or chewable tablets. Shake the suspension well before use. Adults and children over 12 years may take 10–20 mL suspension or 1–2 tablets after meals and at bedtime, or as directed by their doctor. Do not take within 2 hours of other medications as the raft may hamper their absorption. Do not exceed the recommended dose. If your symptoms persist beyond 2 weeks, consult a doctor.

Normally, the lower oesophageal sphincter (LES) (a muscular valve between the stomach and food pipe) stays closed, preventing stomach acid from travelling upward. In reflux, this valve relaxes at the wrong time or stomach pressure rises too high, allowing acidic contents to flow back up into the food pipe. Since the food pipe has no protective lining, it gets damaged by the acid.

As soon as sodium bicarbonate reaches the stomach, it reacts with in a simple acid-neutralisation reaction, producing water and carbon dioxide gas. This quickly reduces the acidity of the stomach contents and releases carbon dioxide bubbles in the process.

Then the chemical groups of sodium alginate (a gel-forming molecule) absorb hydrogen ions and change their charge, causing the alginate molecules to stick together and form a thick, cohesive gel. At the same time, calcium carbonate reacts with stomach acid, dissolving and releasing calcium ions. These calcium ions act like bridges between the alginate molecules, binding them tightly together and making the gel significantly stronger and more solid. Calcium carbonate also continues to neutralise any remaining stomach acid as it dissolves.

The carbon dioxide bubbles produced during this process get trapped inside this calcium-reinforced alginate gel, like bubbles trapped in a sponge. This makes the gel much lighter than the stomach contents, making it rise and float on the surface of the stomach, right at the point where the stomach meets the food pipe.

When pressure builds up in the stomach during belching, lying down, or straining, this floating gel raft gets displaced upward instead. The raft is nearly neutral in pH and harmless to the food pipe lining, and is simply swallowed back down. This way, the raft acts as both a physical barrier and an acid-neutralising agent, providing lasting protection against reflux.

• High-calcium dairy foods (MODERATE): Consuming large amounts of dairy along with calcium carbonate increases the risk of hypercalcaemia and milk-alkali syndrome with prolonged use.

• Alcohol (CAUTION): Alcohol relaxes the lower oesophageal sphincter, potentially reducing the effectiveness of the raft barrier and worsening reflux symptoms.

Tetracyclines / Fluoroquinolones

CAUTION

Calcium carbonate chelates these antibiotics, reducing their absorption. Take them at least after 2 hours.

Thyroid hormones

CAUTION

Calcium reduces levothyroxine absorption. Take thyroid medicine at least 4 hours apart.

Bisphosphonates (alendronate)

CAUTION

Calcium impairs bisphosphonate absorption. Do not take simultaneously.

Iron supplements

CAUTION

Calcium carbonate reduces iron absorption. Separate doses by at least 2 hours.

Digoxin

CAUTION

Hypercalcaemia from excessive calcium use can increase the risk of digoxin toxicity.

• Renal impairment: Low calcium and bicarbonate excretion raise the risk of hypercalcaemia and metabolic alkalosis. Use with caution and under medical supervision.

• Hypercalcaemia / Hypercalciuria: Calcium carbonate is contraindicated as it may worsen already high calcium levels and increase renal stone risk.

• Hypertension and heart failure: The sodium content of sodium alginate and sodium bicarbonate may contribute to fluid retention and elevated blood pressure.

• Achlorhydria (absent stomach acid): The raft-forming reaction depends on gastric acid. Efficacy may be reduced in patients with very low or absent acid secretion.

• Nephrolithiasis (kidney stones): High calcium intake can increase the risk of calcium-oxalate stone formation. Avoid long-term high-dose use in susceptible patients.

Excess sodium bicarbonate can cause metabolic alkalosis, presenting as nausea, vomiting, confusion, and tetany. Calcium carbonate overdose may lead to hypercalcaemia and, with concurrent high dairy intake, milk-alkali syndrome. If overdose is suspected, seek immediate medical attention.

Since Instaraft Tablet 10s is taken as needed, a missed dose is typically not critical. Take the missed dose as soon as you remember, unless your next scheduled dose is due soon. Do not double the dose. If heartburn symptoms worsen, take the next dose at the usual scheduled time.