RENNIE EXTRA TABLETS
Active substance(s): ALGINIC ACID / CALCIUM CARBONATE / MAGNESIUM CARBONATE HEAVY
NAME OF THE MEDICINAL PRODUCT
Rennie Extra Tablets
QUALITATIVE AND QUANTITATIVE COMPOSITION
Each chewable tablet contains:
Alginic acid 150mg, calcium carbonate 625mg and heavy magnesium
Excipients: each chewable tablet contains 14 mg sodium as well as sucrose
(230mg) and glucose (555.22 mg).
For a full list of excipients, see section 6.1.
Chewable tablet (tablet)
Off white, speckled circular tablet, flat on both sides with a bevelled edge.
Symptomatic treatment of complaints resulting from gastro-oesophageal reflux
and hyperacidity, such as regurgitation and heartburn.
Posology and method of administration
The usual dose is 2 tablets to be chewed. It should preferably be taken one hour after
meals and before going to bed. An additional dose can also be taken in between in the
case of heartburn. The maximum daily dose of 8 grams calcium carbonate
(corresponding to 12 tablets) should not be exceeded. Only for use by adults and
children over 12 years of age.
As with all antacids, if symptoms persist in spite of therapy, diagnostic measures are
strongly recommended in order to rule out a more serious disease.
For Special warning and precautions for use please also see section 4.4.
Severe renal insufficiency
hypercalcaemia and/or conditions resulting in hypercalcaemia
nephrolithiasis due to calculi containing calcium deposits
hypersensitivity to the active substances or to any of the excipients.
Special warnings and precautions for use
Prolonged use should be avoided.
If the symptoms persist or only partly disappear, further medical advice should
As with other antacids, Rennie Extra tablets may mask a malignancy in the
Rennie Extra tablets should not be used in the following cases:
In general, caution should be exercised in patients with impaired renal
If Rennie Extra tablets are used in such patients, plasma concentrations of
calcium, phosphate and magnesium should be monitored regularly.
In general calcium containing antacids should be carefully administered in
patients with constipation, haemorrhoids and sarcoidosis.
Prolonged use of high doses may result in undesirable side-effects such as
hypercalcaemia, magnesaemia and the milk alkali syndrome, particularly in
patients suffering from renal insufficiency. The product should not be taken
with large amounts of milk or dairy products.
Prolonged use increases the risk of formation of renal calculi.
In the literature a possible relationship between calcium carbonate and
appendicitis, gastrointestinal haemorrhage, intestinal blockage, or oedema has
been reported in single cases.
Patients with rare hereditary problems of fructose intolerance, glucosegalactose malabsorption or sucrase-isomaltase insufficiency should not take
If symptoms persist after seven days, the clinical situation should be reviewed
by a healthcare professional.
Interaction with other medicinal products and other forms of interaction
Changes in the level of acidity of gastric juice such as those caused by taking antacids
may affect the degree and speed of absorption of medicines administered
concomitantly. It has been shown that antacids containing calcium and magnesium
can hinder the absorption of some antibiotics (such as the tetracyclines and
quinolones); cardiac glycosides (e.g. digoxin, digitoxin); levothyroxine and
Calcium salts reduce the absorption of fluoride and iron containing products, and
calcium salts and magnesium salts can hinder the absorption of phosphates.
Thiazide diuretics reduce the urinary excretion of calcium. Due to increased risk of
hypercalcaemia, serum calcium should be regularly monitored during concomitant
use of thiazide diuretics.
In view of possible changes in the rate of absorption of medicines taken
concomitantly, it is recommended that antacids are not administered at the same time
as other medicines but taken 1 to 2 hours later.
Effects on laboratory parameters:
The administration of antacids may interfere with physiologic values/analytics:
urinary system pH may increase while serum concentration of phosphates and
potassium may decrease with excessive and prolonged use.
Fertility, pregnancy and lactation
No increased risk of congenital defects has been observed after the use of calcium
carbonate, magnesium carbonate and alginic acid during pregnancy. In case of high or
prolonged doses or renal insufficiency, the risk for hypercalcaemia and/or
hypermagnaesia can not be completely excluded.
Rennie Extra tablets can be used during pregnancy if taken as instructed but
prolonged intake of high dosages should be avoided. Rennie Extra tablets can be used
during lactation if taken as instructed.
During pregnancy and lactation, it has to be taken into account that Rennie Extra
tablets provide a substantial amount of calcium in addition to dietary calcium intake.
For this reason, pregnant women should strictly limit their use of Rennie Extra
chewable tablets to the maximum recommended daily dose and avoid concomitant,
excessive intake of milk and dairy products. This warning is to prevent calcium
overload which might result in milk alkali syndrome.
Effects on ability to drive and use machines
Rennie Extra tablets are not expected to affect these functions.
Immune System Disorders:
Hypersensitivity reactions have very rarely been reported. Clinical symptoms may
include rash, urticaria, angioedema and anaphylaxis.
Metabolism and nutrition disorders:
Prolonged use of high doses may possibly result in hypermagnesaemia or
hypercalcaemia and alkalosis (GI symptoms such as nausea and vomiting, fatigue,
confusion, polyuria, polydypsia, dehydration), particularly in patients with impaired
renal function. Prolonged use of high doses of calcium carbonate with milk may lead
to Burnett syndrome (milkalkali syndrome).
Nausea, vomiting, stomach discomfort and diarrhoea may occur.
Musculoskeletal and Connective Tissue Disorders:
Muscular weakness may occur.
Undesirable effects only occurring in the context of milk-alkali syndrome (see
Ageusia may occur in the context of milk-alkali syndrome.
General Disorders and Administration Site Conditions:
Calcinosis and asthenia may occur in the context of milk-alkali syndrome.
Nervous System Disorders:
Headache may occur in the context of milk-alkali syndrome.
Renal and Urinary Disorders:
Azotemia may occur in the context of milk-alkali syndrome.
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is
important. It allows continued monitoring of the benefit/risk balance of the medicinal
product. Healthcare professionals are asked to report any suspected adverse reactions
via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard.
Especially in patients with impaired renal function, prolonged use of high
doses of calcium carbonate and magnesium carbonate can result in renal
insufficiency, hypermagnesemia, hypercalcemia and alkalosis, which may
give rise to gastrointestinal symptoms (nausea, vomiting, constipation) and
muscular weakness. In these cases the intake of the product should be stopped
and adequate fluid intake encouraged. In severe cases of overdosage (e.g.
milk-alkali syndrome) other measures of rehydration (e.g. infusions) might be
Pharmacotherapeutic group: Antacids, other combinations,
ATC code: AO2 AX
Rennie Extra tablets are a combination of two antacids (calcium carbonate and
magnesium carbonate) and an alginic acid.
The mode of action of Rennie Extra tablets is local and is not dependent on
Calcium carbonate has a rapid, long-lasting and powerful neutralising action.
This effect is increased by the addition of magnesium carbonate which also
has a strong neutralising action.
In healthy volunteers, a significant increase in the pH of stomach contents was
achieved within 2 minutes. The total neutralising capacity of two tablets of the
product is 29 mEq/H+(titration to end-point pH 2.5). Apart from the
neutralising action of the antacids, the alginic acid present in Rennie Extra
tablets cause a viscous gel to be formed which floats on the stomach contents
and acts as a physical barrier against reflux.
Calcium and magnesium
In the stomach: calcium carbonate and magnesium carbonate react with the acid in
the gastric juice, forming water and soluble mineral salts.
Calcium and magnesium can be absorbed from these (soluble) salts.
However, the degree of absorption is dependent on the patient and the dose. Approx.
10% calcium and 15-20% magnesium is absorbed.
The small quantities of calcium and magnesium absorbed are usually excreted rapidly
via the kidneys in healthy individuals. In the case of impaired renal function, serum
concentrations of calcium and magnesium may be increased.
Due to the effect of various digestive juices outside the stomach, the soluble salts are
converted to insoluble salts in the intestinal canal and then excreted with the faeces.
After oral ingestion, alginic acid is not converted in the gastro-intestinal tract; 80100% of the quantity ingested is excreted. Absorption of alginic salts is negligible.
Preclinical safety data
List of excipients
Sodium hydrogen carbonate
Lemon cream flavour (primarily composed of lemon oil, lime oil, orange oil, lmenthole, vanilline, maltodextrin, gum arabic, ascorbic acid,
Peppermint flavour (primarily composed of peppermint oil, maltodextrin, gum
arabic, silicon dioxide)
Special precautions for storage
Do not store above 30°C. Store in the original package in order to protect from
Nature and contents of container
Strips consisting of LDPE/Aluminium foil.
Pack-sizes 12, 18, 24, 30 & 36 tablets.
Not all pack sizes may be marketed.
Special precautions for disposal
No special requirements.
MARKETING AUTHORISATION HOLDER
Trading as Bayer plc, Consumer Care Division
MARKETING AUTHORISATION NUMBER(S)
DATE OF FIRST AUTHORISATION/RENEWAL OF THE
30th January 2007
DATE OF REVISION OF THE TEXT
Source: Medicines and Healthcare Products Regulatory Agency
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