How to take ferrous sulfate: Ferrous Sulfate Oral: Uses, Side Effects, Interactions, Pictures, Warnings & Dosing
Ferrous sulfate: 7 things you should know
Medically reviewed by Carmen Fookes, BPharm. Last updated on July 14, 2022.
1. How it works
- Ferrous sulfate is an iron salt that is commonly used as an iron supplement.
- Iron supplements are used to treat or prevent iron-deficiency anemia. In iron deficiency anemia, a lack of iron reduces the production of hemoglobin. Hemoglobin allows red blood cells to transport oxygen around the body as well as giving red blood cells their color.
- Only the iron component of the iron salt is utilized; therefore, iron supplements usually state the amount of the iron salt (for example, ferrous sulfate 325mg) and the equivalent amount of elemental iron (for ferrous sulfate 325mg this equates to 65mg of elemental iron).
- Ferrous sulfate is a mineral and it belongs to the group of medicines known as iron supplements.
- Ferrous sulfate is an iron supplement that may be used to reverse or prevent anemia and replenish iron stores.
- May be used to aid dietary needs.
- May be used off-label to treat restless legs syndrome.
- Although only 10-15% of ferrous sulfate is absorbed, this rate is comparable to that of ferrous gluconate and ferrous fumarate. All of the iron salts have a similar rate of gastrointestinal side effects.
- Ferrous sulfate is usually inexpensive.
- Available as capsules, tablets, and a liquid.
- Immediate-release preparations are preferred for the treatment of iron deficiency anemia because enteric-coated or extended-release preparations are poorly absorbed.
- Generic ferrous sulfate is available.
If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:
- Abdominal discomfort, black or dark stools, constipation, diarrhea, heartburn, nausea, and vomiting, are the most common side effects. The risk of side effects increases with higher dosages.
- The optimal duration of iron supplementation is not known; however, most experts recommend continuing iron supplementation for three months after normalization of hemoglobin in order to replenish iron stores.
- Accidental ingestion of iron supplements, such as ferrous sulfate, is a leading cause of deadly poisoning in children younger than 6 years old. Advise all people taking iron supplements to keep them out of reach of children, and if ingested accidentally, to contact a poison control center immediately.
- Few studies have actually been conducted on the safety and efficacy of iron supplements, including ferrous sulfate. However, a select committee on Generally Recognized as Safe (GRAS) substances concluded that there is no reason to suspect iron supplements are a hazard to the public when they are used as they are now used in current practice. Ferrous sulfate is not FDA approved.
- The low absorption rate of ferrous sulfate and other iron salts means that three times daily dosing may be necessary in order to reverse iron deficiency.
- Enteric-coated preparations may not be as well absorbed as well as liquid preparations.
- Iron supplements may not be suitable for people with a history of ulcers, colitis, or intestinal disease. People with porphyria, thalassemia, hemolytic anemia, who excessively drink alcohol, or women who are pregnant should talk to their doctor before taking iron supplements.
- Ferrous sulfate liquid may cause discoloration of teeth.
- Should not be given to people receiving frequent blood transfusions. Avoid in premature infants until vitamin E stores (deficient at birth) are replenished.
- Ferrous sulfate tablets are not recommended for children aged less than twelve.
- May interact with a number of other medications including some antibiotics, antacids, and other supplements, particularly those that contain calcium, phosphorous, or zinc.
- Maternal iron requirements increase during pregnancy and untreated iron deficiency may be associated with adverse fetal events, such as low birth weight, premature delivery, or increased perinatal mortality.
Note: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. View complete list of side effects
- Ferrous sulfate is an iron supplement that may be used to prevent or treat iron-deficiency anemia. Gastrointestinal side effects are common.
- Ferrous sulfate is available as regular, coated, extended-release tablets and capsules and also as an oral liquid. Swallow iron tablets and capsules whole; do not crush, open, or chew.
- The usual dosage of ferrous sulfate for iron deficiency is three times daily, one hour before or two hours after meals. However, your doctor may advise a lower dosage for you if you are older or if you develop significant gastrointestinal side effects. Follow your doctor’s instructions.
- Administering iron with meals impairs absorption by about 50% and it is uncertain whether this resolves any gastrointestinal side effects.
- Some iron products contain tartrazine. If you are allergic to tartrazine, tell your doctor.
- Even though your iron deficiency may resolve within a few weeks, take ferrous sulfate for the recommended duration to ensure your iron stores are replenished.
- Use the dropper provided with ferrous sulfate drops in order to measure the correct dose. Place the drops directly in the mouth or mix with water or fruit juice (do not use milk).
- Taking iron supplements with vitamin C may help improve absorption rates by as much as 48%.
- Iron supplements, including ferrous sulfate, may interact with some medications including some antibiotics, antacids, and other supplements. These medicines need to be separated by several hours to ensure adequate iron absorption. Talk with your pharmacist about how best to space your medicines.
- Ferrous sulfate should be taken in conjunction with dietary changes that ensure your diet contains adequate amounts of iron-rich seafood or vegetables, meat (particularly red meat), and iron-fortified foods.
- Mixing liquid ferrous sulfate with water or fruit juice and then sipping the mixture through a straw may help prevent teeth staining. Baking soda rubbed on the teeth once a week may help limit any staining that does occur.
- Keep iron supplements well out of reach of children as accidental iron overdosage in children is common and can be fatal.
- Do not take iron supplements for longer than 6 months unless your doctor has advised you to do so.
- Do not take any other medications including those bought over the counter without first checking with your doctor or pharmacist that they are compatible with ferrous sulfate because it may prevent other medications from being absorbed by the body.
- Tell your doctor if you are breastfeeding, pregnant, or intending to become pregnant because you will need to discuss the benefits and risks of using iron supplements during pregnancy and breastfeeding.
6. Response and effectiveness
- A rise in hemoglobin levels should be expected within three weeks of therapy. An increase in hemoglobin by 1g/dL after one month is considered an adequate response. However, experts recommend therapy continue for at least three months to replenish iron stores.
Medicines that interact with ferrous sulfate may either decrease its effect, affect how long it works, increase side effects, or have less of an effect when taken with ferrous sulfate. An interaction between two medications does not always mean that you must stop taking one of the medications; however, sometimes it does. Speak to your doctor about how drug interactions should be managed.
Common medications that may interact with ferrous sulfate include:
- alpha-lipoic acid
- antacids, such as those that contain aluminum, calcium, magnesium, or sodium bicarbonate
- antibiotics, such as doxycycline, minocycline, and tetracycline
- bisphosphonates, such as alendronate, risedronate
- cefdinir (may make stools appear red)
- HIV medications, such as bictegravir, dolutegravir, emtricitabine, or tenofovir
- other iron-containing substances, such as iron dextran, iron sucrose, and ferric carboxymaltose
- Parkinson’s disease medications, such as levodopa or methyldopa
- proton pump inhibitors, such as esomeprazole, lansoprazole, or omeprazole
- quinolone antibiotics, such as ciprofloxacin, norfloxacin, or ofloxacin
- vitamin E.
Iron supplements may affect the results of some laboratory tests.
Note that this list is not all-inclusive and includes only common medications that may interact with ferrous sulfate. You should refer to the prescribing information for ferrous sulfate for a complete list of interactions.
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Related treatment guides
- Iron Deficiency Anemia
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- Vitamin/Mineral Supplementation and Deficiency
- Vitamin/Mineral Supplementation during Pregnancy/Lactation
- Ferrous sulfate. Revised 08/2021. Boca Pharmacal, LLC. https://www.drugs.com/pro/ferrous-sulfate-tablets.html
Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use ferrous sulfate only for the indication prescribed.
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Iron Supplements: MedlinePlus Drug Information
pronounced as (fer’ us)
Accidental overdose of products containing iron is a leading cause of fatal poisoning in children under the age of 6. Keep this product out of the reach of children. In case of an accidental overdose, call your doctor or a poison control center immediately.
Iron (ferrous fumarate, ferrous gluconate, ferrous sulfate) is used to treat or prevent anemia (a lower than normal number of red blood cells) when the amount of iron taken in from the diet is not enough. Iron is a mineral that is available as a dietary supplement. It works by helping the body to produce red blood cells.
Iron supplements (ferrous fumarate, ferrous gluconate, ferrous sulfate) come as regular, film-coated, and extended-release (long acting) tablets; capsules, and an oral liquid (drops and elixir) to take by mouth. Iron is usually taken with food or immediately after a meal once daily or as directed by your doctor. Take iron at around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take iron exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Iron supplements are available alone and in fixed-combination with vitamins and certain medications. If your doctor has prescribed a medication that contains iron, you should be careful not to take any other supplements or medications that also contain iron.
Swallow the tablets, film-coated tablets, and extended release tablets whole; do not split, chew, or crush them.
Mix the elixir with water or fruit juice to avoid possible teeth staining; do not mix with milk or a wine-based solutions.
Iron drops come with a special dropper for measuring the dose. Ask your pharmacist or doctor to show you how to use it. The drops may be placed directly in the mouth or mixed with water, breastmilk, cereal, formula, or fruit juice. Dispense gently into mouth towards inner cheek; a small amount will remain in the tip. If you are giving iron drops to a child, read the package label carefully to be sure that it is the right product for a child of that age. Do not give iron products that are made for adults to children.
This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.
Before taking an iron supplement,
- tell your doctor and pharmacist if you have previously had trouble tolerating iron products, including ferrous fumarate, ferrous gluconate, ferrous sulfate, any other medications, or any of the ingredients in iron preparations. Ask your doctor or pharmacist for a list of the ingredients.
- tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- if you are taking certain antibiotics such as doxycycline, minocycline (Dynacin, Minolira, Solodyn, Ximino), and tetracycline, take them 2 hours before or 2 hours after iron supplements.
- tell your doctor if you have a certain type of blood disease such as hemolytic anemia (a condition with an abnormally low number of red blood cells). Your doctor may probably tell you not to take an iron supplement.
- tell your doctor if you have or have ever had ulcers or gastrointestinal bleeding.
- tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking an iron supplement, call your doctor.
Unless your doctor tells you otherwise, continue your normal diet.
Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
Iron supplements may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- stomach pain
- teeth staining
Iron supplements may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online (http://www. fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from light, excess heat, and moisture (not in the bathroom).
It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org
Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA’s Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.
In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can’t be awakened, immediately call emergency services at 911.
Symptoms of overdose may include the following:
- stomach pain
- PureFe Plus®
- Folvron® (containing Ferrous Sulfate, Folic Acid)¶
- Ferrous Fumarate
- Ferrous Gluconate
- Ferrous Sulfate
¶ This branded product is no longer on the market. Generic alternatives may be available.
Last Revised – 02/15/2022
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Ferrous vitriol for plant protection against diseases, pests and crop fertilization
Ferrous vitriol is the simple name for ferrous sulfate (formula: FeSO4). Due to the price and availability, it has become widespread. A big plus lies in the fact that it does not affect the taste of the fruit, and does not accumulate in them.
In horticulture, it is used as an insecticide (against insects), a fungicide (against fungus) and a root, foliar fertilizer on poor and depleted soils.
The fertilizer has an inorganic origin, and therefore has been known in agricultural technology for more than a hundred years. During this time, the compound has proven useful in agriculture.
It should not be confused with blue vitriol – they have different effects. A similar name was obtained due to the fact that many substances with sulfur were previously called vitriol. Therefore, it is not correct to compare which is better: copper or iron sulfate.
Like any other agricultural chemical, it must be handled with care. Although iron sulfate is a low-toxic compound, it can still be harmful.
What is ferrous sulfate: composition, properties and rules of use
Active ingredients at once 2: iron and sulfur. Firstly, they are detrimental to pests, and secondly, they are necessary for the normal development of all plants. They affect the condition of the green above-ground part and the yield (quantity and quality of fruits).
Iron sulphate is useful for plants for 3 reasons:
- It helps fight iron deficiency in the soil. The metal that is at the heart of the chemical is easy to digest, which allows you to get a noticeable effect in a few applications.
- Suitable for the prevention of the destruction of parasitic insects that live under the bark. In such cases, it is applied with a sprayer, added to the whitewash mixture. Experienced gardeners advise using it in spring and autumn, regardless of whether there is a risk of pests in your area.
- Ferrous sulfate causes shrinkage of plant soft tissues. This makes it suitable for removing moss, lichen and parasitic fungi from the bark, which are difficult to control with other plant protection products. For example, the effect in the removal of scab, powdery mildew, anthracnose has been proven.
Apply by spray or added to whitewash. Best time to use: in spring before budding or in autumn after leaf fall.
Ferrous vitriol is an inorganic substance. It consists of sulfur (sulfur, S), oxygen (oxygen, O) and iron (ferum, Fe). The first two form the acid residue SO4, which is an integral part of all sulfates. Hence the other names of ferrous sulfate fertilizer – ferrous sulphate. All the elements that are included are useful for plants. The effect of fertilization is clearly visible if you follow the color of the leaves. So, they become greener and brighter.
Iron sulfate is salt. It exists in the form of small crystals of light green or gray-green color. Like most salts, it is highly soluble in water. This property is very useful, because it allows you to apply the substance with a sprayer.
Unopened iron sulphate can be stored indefinitely. Unlike organic chemicals, it does not spoil. If the package has already been opened, the powder should be poured into another container that closes tightly. Such manipulation is necessary to protect from water and exposure to sunlight. Plastic buckets with a lid are well suited for this (paint, primer are stored in such buckets).
Use of ferrous sulfate
The acidity of the vitriol-based solution is safe for plants, but sufficient to fight microorganisms and other pests. Therefore, they are disinfected after pruning or natural injury to branches or tree trunks.
Ferrous vitriol is mostly used in horticulture, less often in horticulture. There are practically no cases when it was useful for houseplants, which are grown in pots, flowers. Apply it to trees, bushes, grapes. When it hits a young shoot or leaf, it causes gradual drying. Do not apply during flowering, so as not to harm the bees, as this will lead to poor pollination. As a result, the yield from fruit trees and berry bushes falls.
The two main uses for ferrous sulfate are as a fertilizer and as a pesticide. A solution for foliar fertilizer is made at the rate of 50 g per 10 liters of water. Suitable for feeding both vegetables and garden plants. Also a good effect shows the introduction of organic matter. For example, 100 g of iron sulfate is added to 10 kg of compost.
As a poison, it is suitable for fighting insects, fungi and lichens. There is more concentration. So, for pests, 500 g of iron sulfate is added to 10 liters of water, against lichens and mosses (appear in large quantities on the bark of old trees) – 300 g.
Less common area of use – spring frosts. The fact is that iron sulfate can slow down the appearance of kidneys. If a sharp cooling is predicted after a thaw, a solution of vitriol is used, due to which the trees “wake up” a week later.
Please note that the positive effect will only be achieved with the correct dosage. To combat various parasites, fertilizers, slow down the development of the kidneys, different concentrations of the substance are used.
Regardless of the area and goal pursued by the gardener, the positive effect of use lasts up to 2 weeks. You also need to be careful when mixing iron sulfate with other active additives. So, calcium significantly impairs its digestibility as a plant. Regularity is important. For example, to control lichen or insects, it is necessary to spray every week for about one month. The manufacturer usually indicates specific concentrations and frequency on the packaging.
Also, iron sulfate cannot be combined with alkaline fertilizers, as they react and neutralize each other.
Make sure the dosage is correct before mixing ferrous sulfate. Use gloves and goggles. Salt is easier to dissolve if it is first dissolved in a small amount of liquid. The process will go better if the water is preheated. Then the resulting mixture is poured into water and stirred. Thus, the solution is good, since the active substance is evenly distributed throughout the entire volume of water. After that, leave the iron sulfate to stand for 20-30 minutes. The resulting liquid will have a light green to bright emerald color.
Since the acidity of the solution is increased, glass or plastic dishes are used for work. They do not react with vitriol, and iron or other metals quickly begin to rust. For the same reason, wooden or plastic spatulas are used for stirring.
Ferrous vitriol in tillage: advantages
Along with high efficiency, one of the important advantages is low price. So, in Ukraine, 1 kg of iron sulfate can be bought for 10-25 hryvnias. Thus, based on the average price, a large number of plants can be processed cheaply, which is important for farmers who maintain extensive gardens.
The range of applications is not limited to fruit trees. Also, iron sulfate is suitable for fertilizing vegetable crops, less often used by flower growers. It allows you to fight with all the parasites that you may encounter in the temperate climate zone.
But perhaps the biggest advantage of ferrous sulfate is its low toxicity. The substance is inorganic, which means that it easily breaks down in natural conditions. Iron does not accumulate in the fruits of plants, and therefore will not harm the body when eating them.
Ferrous vitriol in tillage: cons
Fertilizer also has disadvantages. They are related to the dosage, the limited period of use and the risks that arise when working with young plants.
Iron sulfate can be diluted in different concentrations. For 10 liters it can be added from 50 g to half a kilogram. The effect that will be obtained in the end will depend on the amount of active substance.
Lowest iron sulfate content when used as fertilizer. If it is necessary to disinfect the damage, then 10 g of vitriol is added to 1 liter of water (the usual ratio is 100 g per 10 liters, but usually there will be a lot of this amount for disinfection). Most of the powder is spent on the destruction of insects – 500 g per 10 liters, and lichens – 300 g per 10 liters. You can buy insecticides that effectively destroy pests at Bizon-Tech.
Rapid liquid oxidation
Another disadvantage of ferrous sulfate is the relatively short period of effectiveness. After application to the bark of the plant, the positive effect will last from 10 to 14 days. This is due to the fact that after dissolving in water, the drug begins to actively react with oxygen, which is one of the constituent substances of the air. As a result, vitriol is transformed (turns into ferric sulfate) and completely loses its beneficial properties.
The frequency of application is related to this factor: in order to achieve the desired effect, the procedure is repeated after 5-7 days.
Risks during treatment in spring
According to the instructions, iron sulphate is used for prevention twice a year: in spring and autumn. This time is chosen to minimize the likelihood of harm, because when it hits the green parts, sulfate causes them to die off.
Be especially careful in spring. After the appearance of the kidneys, the branches cannot be processed with iron sulphate. It is permissible to apply it only to the stiffened parts. The danger to leaves and shoots is due to the fact that the aqueous solution of vitriol has a high acidity. Even in a 2% solution, there is enough acid to cause burns, wilting, and even complete death of a young plant.
Contents up to 1% do no harm, but the positive effect is also practically not noticeable. From this follows the conclusion that it is necessary to breed iron sulfate according to the instructions. Moreover, the ratio in the recipe will differ from the purpose (fertilizer or pest control) and the time of application.
Iron sulfate is one of the most important substances for the gardener in the fight and prevention of fungal diseases and pests. Fertilizer helps to solve the problem of iron deficiency in the soil, allows you to maintain high yields during spring frosts.
When using the substance, the following rules must be observed:
- observe the dosage;
- wear gloves and goggles;
- do not apply to leaves and young shoots.
If these recommendations are followed, ferrous sulfate will be useful as both a fertilizer and a pesticide.
Ferrous vitriol (iron sulfate II). Chemistry for industry. … Producer Russia
|Country of origin||Russia|
|Chemical formula||FeSO₄ 7H₂O|
|Shelf life||2 years|
|Appearance||Grey-green crystals or powder|
Technical iron sulphate 7-water (iron (II) sulfate heptahydrate, ferrous sulfate) is produced in the form of transparent crystals or gray-green powder. Ferrous vitriol is highly soluble in water, the solubility is 26.3 g per 100 ml of water at 20°C. The mass fraction of ferrous sulfate in technical iron sulphate ranges from 47 to 53% for the first and second grades, respectively. It has low toxicity.
Iron sulfate is mainly used in the textile industry for dyeing fibers, in agriculture as a fungicide for treating cultivated plants, and in medicine as a medicine.
In summer cottages and construction
Iron vitriol is used for biocidal treatment of surfaces made of various materials in order to prevent the appearance of molds and lichens. In home gardening and construction, iron sulfate is used to impregnate lumber and finished wooden buildings to get rid of mold, the reagent does not cause corrosion of metal structures, unlike copper sulfate, but has weaker antiseptic properties.
In summer cottages, iron sulphate is used to disinfect cesspools and toilets, treat cellars, and concrete tiles.
In horticulture and horticulture
Iron sulfate is widely used in horticulture as a fertilizer and as a plant pest control . This reagent is less toxic than copper sulphate and is often used to prevent chlorosis, and to combat diseases such as scab, powdery mildew, gray and fruit rot, grape oidium, scab of apple and pear trees, anthracnose, coccomycosis, black cancer, lichens and tree moss.
When whitewashing tree trunks, treating damage, prepare a 1% aqueous solution of ferrous sulfate, then spray the plants with it.
For preventive treatment of plants in the spring, a 5% solution of ferrous sulfate is prepared, which is used to treat branches.
To control lichen and moss use a 0.3% solution.
Ferrous vitriol is used as a source of iron , which is necessary for plant development, this is especially true for iron-poor and acidic soils. Crops such as tomatoes, potatoes, cabbage, pears, and apple trees suffer greatly from iron deficiency.
Iron sulfate should not be mixed with lime, as this forms water-insoluble compounds that interfere with plant metabolism. Also, the reagent is incompatible with organophosphorus substances and substances that decompose in an alkaline environment.
- The substance is slightly toxic to the skin, but hazardous in contact with eyes and mucous membranes;
- In case of contact with mucous membranes or eyes, rinse with water for at least 10 minutes and seek medical advice if necessary;
- Keep out of the reach of children;
Reagent should only be stored in a tightly closed container. When ferrous sulfate is oxidized by atmospheric oxygen, its fungicidal properties are lost. Keep away from prolonged exposure to sunlight. If the storage conditions are observed, the shelf life is not limited.
Physical and chemical indicators
|Name of the indicator||Norm for GOST 6981-94|
|First grade||Grade II|
|Appearance||Greenish blue crystals|
|Mass fraction of iron sulfate, %, not less than||53||47|
|Mass fraction of free sulfuric acid, %, not more than||0.3||1.0|
|Mass fraction of substances insoluble in water, %, not more than||0.2||1.0|
|Hazard class according to the degree of exposure to the human body||3|
|Explosion and fire hazard|| Technical iron sulphate is non-flammable and fire- and explosion-proof.|