Medication
There are 4 major classes of drugs to treat the acid element of acid reflux.
In ascending order of effectiveness, they are antacids, alginates, H2 blockers and Proton Pump Inhibitors.
If you need to use any of these drugs frequently,
please seek medical advice.
Antacids
They work immediately on excess acid. They do not prevent excess acid occurring.
These are drugs that neutralise the acid. Most commonly they are made of chalk, calcium carbonate. Examples are Tums or Rennie. Chemically, this reaction takes place:
NaHCO3 + HCl → NaCl + H2O + CO2
(Sodium bicarbonate + Hydrochloric acid gives Sodium Chloride (table salt) plus water and carbon dioxide).
Alginates
Gaviscon is the brand name of the white milky liquid that floats on the stomach contents as oil floats on water to reduce the possibility of reflux whilst also providing a temporary protective film to the lower oesophagus and neutralising the acid with an antacid component. (Some generic versions are now available.)
H2 blockers
Histamine H2 Receptor Antagonists work to block the (histamine H2) signals that tell the stomach to produce acid. (N.B. This is not the same as an antihistamine which blocks histamine H1).
The most common is Ranitidine, brand name Zantac but others are available as shown below.
These work proactively to reduce the amount of acid rather than being an instant antacid. Often prescribed to be taken in the evening to reduce nighttime reflux of acid.
(Other H2 blockers: Lafutidine, Loxtidine, Niperotidine, Roxatidine.)
* Please note doses shown are not guaranteed to be equivalent. Do not assume because a dose is shown it is the safe dose. It may vary according to age and body build.
Proton Pump Inhibitors (PPIs)
These are the most effective drugs to reduce acid production. They work by effectively stopping the production of some of the cells (proton pumps) that produce acid in the stomach.
There are a number known by different names as shown in the table below. The equivalent dose shown is the "maintenance dose" though you may be prescribed a higher dose initially. They are proactive drugs and are most effective after taking them for a few days. They do not neutralise acid already produced.
PPI (Proton Pump Inhibitor) drugs
(Other PPIs: Ilaprazole, Picoprazole, Tenatoprazole, Timoprazole)
Do not assume because a dose is shown it is the safe dose. It may vary according to age and body build.
The most common brand names are shown though they may also be known under other names in other parts of the world.
Prices thanks to Newcastle Regional drug & Therapeutics Centre (August 2018)
Research evidence has shown all PPIs are as effective as each other (though the drugs companies may try to make us believe otherwise) but some may be better tolerated by some patients. [a-iv][a-v]
* Astra Zeneca (who make the drug) claims 40mg esomeprazole is equivalent to 20mg omeprazole and one (Astra Zeneca sponsored) trial showed 40mg esomeprazole was better at reducing acid production than 20mg omeprazole. [a-vi]
Another study published February 2015 [a-vii] also compared 40mg esomeprazole with 30mg lansoprazole and 40mg Pantoprazole finding: "esomeprazole was more effective".
Research funded by Reckitt Benkiser (who make the drug) found Gaviscon was no less effective than standard dose omeprazole for a 24hr period. [a-viii]
Potassium Competitive Acid Blockers (PCABs)
Not in the printed book since they've only come onto the scene more recently.
Similar to PPIs, the first PCAB is Vonoprazan.
This paper in Gastrointestinal Pharmacology and Therapeutics from 2018 provides a very good initial overview: Potassium-competitive acid blockers - are they the next generation of proton pump inhibitors?
"There have been tremendous changes in the treatment of acid-related diseases. In this rapidly evolving field, novel drugs such as potassium-competitive acid blockers (P-CABs) show promising potential. This review aims to provide a perspective on this new class of drugs by summarizing the mechanism of action, therapeutic benefits, adverse effects and approval status of various P-CABs in the market."
This study was published in Medical Science Monitor in 2019: Comparison of the Use of Vonoprazan and Proton Pump Inhibitors for the Treatment of Peptic Ulcers Resulting from Endoscopic Submucosal Dissection: A Systematic Review and Meta-Analysis
"The findings of the systematic review and meta-analysis showed that the efficacy of vonoprazan was comparable with PPIs for the treatment of peptic ulcers following ESD. Further studies are required to support the safety and efficacy of vonoprazan compared with different types of PPIs. "
This study was published in Gastroenterology in October 2022: "Vonoprazan versus Lansoprazole for Healing and Maintenance oh Healing of Erosive Esophagitis: A Randomized Trial"
"Vonoprazan was non-inferior and superior to the PPI lansoprazole in healing and maintenance of healing of erosive esophagitis. This benefit was seen predominantly in more severe erosive esophagitis."