Author: Guangdong Pharmaceutical Association Dongguan People's Hospital Liang Baofang
There are pregnant women consulting pharmacists:
The doctor said that there was a bit of anemia, prescribed iron supplements, but felt that there were no symptoms, not serious, whether it was possible to take medicine, after all, it was better to take less medication during pregnancy.
Why should iron be supplemented during pregnancy, and how should iron supplementation be supplemented? I will explain it in detail for you.
<h1 class="pgc-h-arrow-right" data-track="87" > Why should iron supplementation for anemia in pregnancy? </h1>
The World Health Organization recommends that when the concentration of haemoglobin in pregnancy < 110 g/L, it can be diagnosed with pregnancy with anemia.
According to the Hb level, it is divided into:
■ Mild anemia (100~109g/L)
■ Moderate anemia (70~99g/L)
■ Severe anemia (40~69g/L)
■ Very severe anemia (<40g/L)
Guidelines recommend that serum ferritin concentrations < 20 μg/L to diagnose iron deficiency.
Anemia in pregnancy is more common, the prevalence of iron deficiency anemia (IDA) in pregnant women in China is 19.1%, and the prevalence of IDA in the early, middle and third trimesters of pregnancy is 9.6%, 19.8% and 33.8%, respectively, mainly iron deficiency anemia. Fatigue is the most common symptom of IDA, and people with severe anemia have symptoms of pallor, fatigue, palpitations, dizziness, dyspnea, and irritability. Anemia during pregnancy leads to a decrease in the body's resistance and is prone to infectious diseases. If the anemia is serious, it is prone to hypertension and heart disease during pregnancy, heart failure is easy to occur during childbirth, and it is easy to be infected after childbirth. The effects on the fetus are preterm birth, stillbirth, and the effects on the baby are anemia, brain dysplasia, and mental retardation. And with the development of pregnancy, in the middle and third trimesters of pregnancy, the demand for iron will be more and more, and if iron is not supplemented in time, it will aggravate the disease.
<h1 class="pgc-h-arrow-right" data-track="88" > general management principles for anemia in pregnancy</h1>
Iron deficiency and mild and moderate anemia are mainly treated with oral iron, and diet is improved, and iron-rich foods are eaten. Patients with severe anemia are treated with iron or injections, and can also be infused with concentrated red blood cells in small quantities and multiple times. Patients with very severe anemia are preferred for concentrated red blood cell transfusion, and after the Hb reaches 70 g/L and symptoms improve, they can be changed to oral iron or injectable iron. Oral iron should be continued for 3 to 6 months or up to 3 months postpartum after treatment until Hb returns to normal [2].
<h1 class="pgc-h-arrow-right" data-track="89" > dietary guidance for anemia in pregnancy</h1>
Through dietary guidance can increase iron intake and iron absorption, focusing on food diversification and reasonable collocation, IDA patients can increase iron-rich foods such as heme iron-containing foods such as red meat, fish and poultry, while increasing the intake of fruits, potatoes, green leafy vegetables, cauliflower, carrots and cabbage and other vitamin C-rich foods can promote iron absorption. However, it should be noted that milk and dairy products can inhibit iron absorption, and other foods that inhibit iron absorption include grain bran, cereals, high-precision flour, beans, nuts, tea, coffee, cocoa and so on.
<h1 class="pgc-h-arrow-right" data-track="90" > oral iron for anemia in pregnancy</h1>
Pregnant women diagnosed with IDA should be supplemented with elemental iron 100 to 200 mg/day, and Hb should be reviewed after 2 weeks of treatment to assess efficacy, usually with an increase in Hb levels of 10 g/L after 2 weeks and an increase of 20 g/L after 3 to 4 weeks.
There are many varieties of oral iron, each with different iron content and action characteristics, as follows:
Commonly used oral iron and its usage
1. The first generation of inorganic iron
Ferrous sulfate 300 mg/tablet
Elemental iron content: 60mg / tablet
Supplemental elemental iron amount: 60 mg / time, 3 times / day
Features: Gastrointestinal irritation is large, there is a great rust smell.
2, the second generation - small molecule organic iron agent
(1) Ferrous fumarate 200mg/tablet
Supplemental elemental iron volume: 60-120 mg /time, 3 times/day
Features: Faster onset of action, fewer adverse reactions, but poor taste.
(2) Ferrous succinate 100mg/tablet
Elemental iron content: 30 mg / tablet
Features: The efficacy is higher than other iron agents, the absorption is stable, the adverse reactions are small, and the irritation to the gastric mucosa is small.
(3) Ferrous gluconate 300mg/tablet
Elemental iron content: 36mg / tablet
Supplemental elemental iron volume: 36-72 mg /time, 3 times/day
Features: Absorption is susceptible to food, fast onset of action, gastrointestinal reaction is lighter.
3, the third generation - polysaccharide iron complex
Polysaccharide iron complex 150 mg/tablet
Elemental iron content: 150mg / tablet
Supplemental elemental iron volume: 150-300 mg / time
Features: absorbed in molecular form, good bioavailability, not affected by stomach acid reduction and food.
Precautions for oral iron: In order to avoid food hindering the absorption of iron, it is advisable to take iron 1 hour before meals, but some iron agents will irritate the gastrointestinal tract and need to be taken after meals. Do not lie flat or on your side when taking the drug, stand, drink more water, and avoid drug adhesion to the esophagus and cause esophageal irritation. Milk and dairy products, checks, coffee, cocoa, etc. hinder iron absorption, so drink milk, tea, coffee, etc. should be separated from iron by 1 hour. If black stools appear during the medication, they will return to normal after stopping the medication, so don't worry.
<h1 class="pgc-h-arrow-right" data-track="92" > injection of iron for anemia during pregnancy</h1>
Injectable iron may be an option for those who cannot tolerate oral iron, have uncertain adherence, or who are ineffective in oral iron.
Formula for dosage of injectable iron is calculated:
Total injectable iron dose (mg) = body weight (kg) × (Hb target value - actual value of Hb) (g/L) ×0.24 + stored iron (500 mg).
1. Adverse reactions
The main adverse reactions of iron injections are pain at the injection site, headache and dizziness, and occasionally fatal allergic reactions.
2. Classification
Commonly used injectable iron sucrose and iron dextran, iron sucrose is currently considered to be the safest, and iron dextran may have serious adverse reactions, therefore, considering the safety and pharmacokinetic characteristics, the "Patient Blood Management - Preoperative Anemia Diagnosis and Treatment Expert Consensus 2018" recommends the use of iron sucrose [3].
3. Precautions
Non-enteric iron is not recommended for pregnant women under 3 months of pregnancy. Ferrosucrose is recommended for intravenous administration by instillation or slow injection, or directly into the intravenous end of the dialyzer, and is not suitable for intramuscular injection.
When administered intravenously, the recommended rate of instillation is: 100 mg of iron for at least 15 minutes, 200 mg of iron for at least 30 minutes, 300 mg of iron for at least 1.5 hours, 400 mg of iron for at least 2.5 hours, and 500 mg of iron for at least 3.5 hours.
Table 2 Specifications and iron content of commonly used iron injections
Review expert: Wu Xinrong, chief pharmacist of the General Hospital of the Southern Theater
The above is the original work of the volunteers of the "Drug Safety Cooperation Alliance", if you reprint, please indicate the author and source!
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