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Rennie in pregnancy
Medical expert of the article
Last reviewed: 04.07.2025
Rennie during pregnancy is a drug that is widely used to treat heartburn, which bothers women in the late stages of pregnancy. The safety of this drug for the fetus is widely discussed, but it is also important that its effectiveness is high. Therefore, before using the drug to treat heartburn, it is necessary to know some pharmacological features in order to accurately decide whether it can be taken and under what conditions.
Basic principles of using Rennie during pregnancy
Can Rennie be taken and is this drug harmful during pregnancy? This question is asked by many women who use this drug, but since it has its own characteristics of pharmacological action, it is necessary to take into account different options and individual characteristics of the woman.
Pregnancy is a period when another life develops in a woman's body and at this time it is necessary to be very careful about nutrition and taking any pharmacological drugs. The process of organogenesis begins in the first trimester, and then the growth and differentiation of tissues continues, which also requires increased attention to taking any drugs.
The fetus is an agent foreign to the woman's body, because it contains 50% of the information from the father. The woman's immune system perceives it as an antibody to some extent, therefore, until the formation of its own placenta with an individual barrier and blood flow, a state of relative immunosuppression develops. This condition of a pregnant woman contributes to a change in all reactions of the female body, which could have been normal before. That is, the reactions of pharmacological transformation of drugs also occur differently, which can thus significantly affect the child. This is especially true for the first trimester of pregnancy, when there is no placenta yet, as an individual defense mechanism. This is what the peculiarities of using Rennie at different stages of pregnancy are associated with.
Rennie is not recommended for use during early pregnancy, as is any other medication, since the instructions state that there are no contraindications for use, but it must be used with caution and in the correct dosage.
Rennie can be used without fear during late pregnancy, which often happens, since it is in the third trimester of pregnancy that changes in the normal functioning of the gastrointestinal tract are observed in the form of heartburn. This is due to the fact that the digestive system during pregnancy due to the influence of hormones - prostaglandins - changes in such a way that hypotension of the gastrointestinal tract occurs. In this case, the lower esophageal sphincter cannot contract normally and its atony or involuntary relaxation occurs, which contributes to the reflux of acidic contents of the stomach. Increased reflux in late pregnancy also occurs due to the enlarged uterus, which presses on the stomach and intestines. This is accompanied by complaints of heartburn, nausea, vomiting. This symptom bothers a woman for a very long time, which forces her to look for methods to solve the problem - folk remedies or medications. Rennie is one of the drugs that can be used in this case.
Pharmacodynamic properties of the drug
The drug is available in chewable tablets with different pleasant fruit flavors, which makes this drug even more attractive, although this is a subjective characteristic.
The mechanism of action of the drug is its protective effect on the stomach and its antacid property. The drug contains active substances in the form of calcium carbonate and magnesium carbonate, due to which the effect of the drug is expressed.
The active components of the drug, after they appear in the stomach, promote the connection with the radicals of hydrochloric acid and as a result it is neutralized with the formation of calcium and magnesium salts. This is how the neutralizing ability of the drug is revealed. An additional effect of Rennie is protective. It is explained by the stimulation of the synthesis of bicarbonates in the stomach cavity under the influence of magnesium, which helps protect the mucous membrane from aggressive factors. The calcium of the drug has the ability to be absorbed into the bloodstream by 10%, and magnesium by 20%, which must be taken into account in case of possible concomitant conditions and drug overdose. The effect of the drug is fast, it occurs 5-10 minutes after using the drug.
Indications for the use of Rennie are intestinal and stomach diseases, which are accompanied by an increase in the basal secretion of hydrochloric acid. Rennie is also recommended in the complex therapy of duodenal and gastric ulcers, as well as a preventive treatment for this pathology. Other indications for use are acute gastroduodenitis, heartburn, Zollinger-Ellison syndrome, dietary disorders, which are accompanied by increased discomfort in the stomach.
Pharmacokinetic properties of the drug
As a result of taking the drug orally, calcium and magnesium salts are formed, which are partially absorbed into the blood, and partially excreted in the feces in a complex of insoluble compounds. The part that is absorbed into the blood is excreted through the kidneys. An increase in the amount of the drug in the blood is possible with violations of their excretion. No direct teratogenic effect of Rennie has been identified; it is able to penetrate the fetoplacental barrier only in the smallest concentrations in the form of calcium and magnesium compounds, which explains its minimal threat to the fetus.
Methods of use and symptoms of overdose
An overdose of the drug may be observed in concomitant kidney diseases, which will manifest itself as a stool disorder such as diarrhea, and in case of chronic overdose, symptoms of elevated calcium levels in the blood occur.
How to use the drug - it must be chewed until completely dissolved. Dosage - one tablet, then after two hours you can take another if the symptoms have not passed. The maximum number of tablets that can be taken during pregnancy should not exceed 16.
The interaction of Rennie with other drugs is that it reduces the absorption of other medications, so the interval between the use of another drug and Rennie should be at least two hours.
Rennie storage conditions are as follows: shelf life is five years. Store at a relative temperature below 25 degrees, avoiding direct exposure to high and low temperatures, and also exclude high humidity. Keep away from children.
Rennie can be successfully used during pregnancy as a symptomatic treatment for heartburn, which often bothers pregnant women in the late stages of pregnancy. It is important to remember that the dosage of the drug should not be exceeded, as side effects are possible. Given the low absorption of the drug into the blood, it can be taken during pregnancy without harm to the fetus.
Contraindications for use and its side effects
Rennie should not be used during pregnancy in case of acute disorders or serious pathologies of the liver and kidneys, as well as in the presence of allergic reactions in the anamnesis or allergy to additional components of the drug. The drug should be prescribed with caution in case of elevated calcium levels in the blood, as there may be an overdose, as well as in the presence of elevated magnesium levels.
Side effects of Rennie during pregnancy in case of its use in the first trimester are possible violations of fetal tissue differentiation and placentation disorders, which have not been proven by clinical trials, there is only a theoretical concept. Allergic reactions may also be detected during the drug intake and changes in the nature of the stool in the form of diarrhea, changes in its color or constipation. Side effects are possible with concomitant renal dysfunction in the form of hypermagnesemia and hyperkalemia. Often there is one of the side effects in the form of the development of the "rebound" syndrome - in this case, the symptoms of heartburn disappear only for a while, and after stopping the drug, the symptoms become even more severe. A side effect in the form of an increase in blood sugar levels in concomitant diabetes is also possible, since the drug contains a significant amount of sucrose.
Attention!
To simplify the perception of information, this instruction for use of the drug "Rennie in pregnancy" translated and presented in a special form on the basis of the official instructions for medical use of the drug. Before use read the annotation that came directly to medicines.
Description provided for informational purposes and is not a guide to self-healing. The need for this drug, the purpose of the treatment regimen, methods and dose of the drug is determined solely by the attending physician. Self-medication is dangerous for your health.