Vitamin A is a fat-soluble vitamin. Its different forms are often called "retinoids." They include retinol, retinal, retinoic acid, and retinyl ester.
Vitamin A is needed for the proper growth and functioning of many parts of the body, including the eyes, skin, and immune system. It can be found in many foods, including fruits, vegetables, and fish. Carotenoids are a group of chemicals found in plants. Some can be converted to vitamin A in the body.
People most commonly use vitamin A for treating vitamin A deficiency. It is also used for aging skin, acne, HIV/AIDS, cataracts, child development, infections, and many other conditions.
- Vitamin A deficiency.  Oral vitamin A is effective for treatment and prevention of vitamin A deficiency.
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- Aging skin.  Topical vitamin A (retinol) formulations seem to improve symptoms of aging skin, such as wrinkles and mottled pigmentation.
Login for details - Measles.  High dose oral vitamin A seems to reduce mortality from measles in children under 2 years of age.
Login for details - Night vision.  Oral vitamin A as retinyl palmitate seems to reduce night blindness during pregnancy in malnourished patients.
Login for details - Oral leukoplakia.  High-dose oral vitamin A seems to reduce oral leukoplakia lesions in patients that chew tobacco and/or betel nut.
Login for details - Overall mortality.  In children at risk for vitamin A deficiency, oral vitamin A seems to reduce mortality. However, it does not seem to reduce mortality in healthy adults.
Login for details - Postpartum complications.  Oral vitamin A seems to reduce postpartum diarrhea and mortality in malnourished patients.
Login for details - Retinitis pigmentosa.  Oral vitamin A supplementation in children with retinitis pigmentosa seems to slow retinal function decline.
Login for details - Ulcerative colitis.  Oral vitamin A supplementation in patients with ulcerative colitis seems to improve clinical response and mucosal healing.
Login for details - Wrinkled skin.  Topical vitamin A (retinol) formulations seem to improve photodamage and wrinkles.
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- Atopic disease.  Supplementation with oral vitamin A does not seem to reduce the risk of atopy.
Login for details - Bronchopulmonary dysplasia.  Intramuscular vitamin A does not seem to reduce the risk of bronchopulmonary dysplasia (BPD) in very low birth weight infants.
Login for details - Fetal and premature infant mortality.  Giving oral vitamin A to malnourished mothers does not seem to reduce fetal, early infant, or first year mortality. Giving oral vitamin A to the infant also does not seem to reduce mortality in most patients.
Login for details - Intestinal parasite infection.  Oral high-dose vitamin A does not seem to prevent reinfection with intestinal parasites.
Login for details - Melanoma.  Oral vitamin A in patients with resected melanoma does not seem to improve survival and disease recurrence.
Login for details - Miscarriage.  Oral vitamin A given to the mother does not prevent miscarriage or stillbirth.
Login for details - Tuberculosis.  Oral vitamin A does not seem to improve tuberculosis disease duration or mortality.
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- Head and neck cancer.  Oral vitamin A taken for 2 years does not seem to improve survival or prevent head and neck cancer recurrence.
Login for details - HIV transmission.  Oral vitamin A does not reduce vertical HIV transmission risk. There is some concern that vitamin A might increase HIV transmission through breast milk.
Login for details - Lower respiratory tract infections.  Oral vitamin A does not reduce the risk for lower respiratory tract infections in children.
Login for details - Pneumonia.  Oral vitamin A does not prevent pneumonia or reduce pneumonia severity in children.
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- Acne.  Although prescription vitamin A analogs are approved to treat acne, it is unclear if non-prescription topical vitamin A products help with acne symptoms.
Login for details - Alcohol-related liver disease.  Oral vitamin A has only been evaluated in combination with other ingredients; its effect when used alone is unclear.
Login for details - Autism spectrum disorder.  It is unclear if oral vitamin A is beneficial for improving symptoms of autism.
Login for details - Breast cancer.  Although dietary vitamin A has been associated with reduced risk for breast cancer, it is unclear if vitamin A supplements are beneficial.
Login for details - Cataracts.  It is unclear if oral vitamin A is beneficial for cataract prevention.
Login for details - Cervical cancer.  It is unclear if oral vitamin A is beneficial for cervical cancer prevention.
Login for details - Chemotherapy-induced diarrhea.  It is unclear if oral vitamin A helps to prevent diarrhea caused by chemotherapy.
Login for details - Child development.  Oral vitamin A might improve growth and development in children with vitamin A deficiency, but not in those with good nutritional status.
Login for details - Chronic obstructive pulmonary disease (COPD).  There is limited evidence on the oral use of vitamin A in patients with emphysema.
Login for details - Colorectal adenoma.  Oral vitamin A has only been evaluated in combination with other ingredients; its effect when used alone is unclear.
Login for details - Colorectal cancer.  It is unclear if oral vitamin A is beneficial for colorectal cancer prevention.
Login for details - Coronary artery bypass graft (CABG) surgery.  It is unclear if oral vitamin A improves recovery after CABG surgery.
Login for details - Esophageal cancer.  It is unclear if oral vitamin A is beneficial for esophageal cancer prevention.
Login for details - Gastric cancer.  It is unclear if oral vitamin A is beneficial for gastric cancer prevention.
Login for details - Genital warts.  It is unclear if topical or oral vitamin A is beneficial for genital wart resolution.
Login for details - HIV/AIDS.  It is unclear if oral vitamin A is beneficial for improving HIV/AIDs outcomes.
Login for details - HIV/AIDS-related diarrhea.  It is unclear if oral vitamin A is beneficial for preventing diarrhea associated with HIV.
Login for details - Infant development.  It is unclear if intramuscular vitamin A improves the development of low birth weight infants.
Login for details - Iron deficiency anemia.  It is unclear if oral vitamin A is beneficial for the prevention or treatment of anemia due to iron deficiency.
Login for details - Leukemia.  It is unclear if oral vitamin A is beneficial for leukemia prevention.
Login for details - Liver cancer.  It is unclear if oral vitamin A is beneficial for liver cancer prevention.
Login for details - Lung cancer.  It is unclear if oral vitamin A is beneficial for lung cancer treatment or prevention.
Login for details - Malaria.  It is unclear if oral vitamin A is beneficial for reducing symptoms of malaria in young children.
Login for details - Multiple sclerosis-related fatigue.  It is unclear if oral vitamin A is beneficial for reducing fatigue in patients with multiple sclerosis.
Login for details - Non-Hodgkin lymphoma.  It is unclear if oral vitamin A is beneficial for non-Hodgkin lymphoma prevention.
Login for details - Nonmelanoma skin cancer.  It is unclear if oral vitamin A is beneficial for nonmelanoma skin cancer prevention.
Login for details - Osteoarthritis.  Oral vitamin A has only been evaluated in combination with other ingredients; its effect when used alone is unclear.
Login for details - Ovarian cancer.  It is unclear if oral vitamin A is beneficial for ovarian cancer prevention.
Login for details - Pancreatic cancer.  It is unclear if oral vitamin A is beneficial for pancreatic cancer prevention.
Login for details - Parkinson disease.  It is unclear if oral vitamin A prevents Parkinson disease development.
Login for details - Photoreactive keratectomy.  Oral vitamin A has only been evaluated in combination with other ingredients; its effect when used alone is unclear.
Login for details - Prostate cancer.  It is unclear if oral vitamin A is beneficial for prostate cancer prevention.
Login for details - Psoriasis.  It is unclear if topical vitamin A is beneficial for psoriasis symptoms.
Login for details - Radiation proctopathy.  It is unclear if oral vitamin A is beneficial for reducing chronic radiation proctopathy symptoms.
Login for details - Retinopathy of prematurity.  It is unclear if oral vitamin A is beneficial for preventing retinopathy of prematurity.
Login for details - Urinary tract infections (UTIs).  It is unclear if adding oral vitamin A to antibiotic therapy is beneficial for symptoms of acute pyelonephritis in young females.
Login for details - Warts.  It is unclear if topical or oral vitamin A improves the resolution of viral warts.
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When taken by mouth: Vitamin A is likely safe when taken in amounts less than 10,000 units (3,000 mcg) daily. Vitamin A is available in two forms: pre-formed vitamin A (retinol or retinyl ester) and provitamin A (carotenoids). The maximum daily dose relates to only pre-formed vitamin A.
Pre-formed vitamin A is possibly unsafe when taken in doses greater than 10,000 units (3,000 mcg) daily. Higher doses might increase the risk of side effects. Long-term use of large amounts might cause serious side effects including mental changes.
When applied to the skin: Vitamin A is possibly safe when used short-term. Retinol 0.5% serum has been used daily for up to 12 weeks without serious side effects.
Special Precautions & Warnings:
Pregnancy and breast-feeding: Vitamin A is likely safe when taken in recommended amounts of less than 10,000 units (3,000 mcg) of pre-formed vitamin A daily. Larger amounts are possibly unsafe and can cause birth defects. Monitor vitamin A intake from all sources during the first three months of pregnancy. Forms of vitamin A are found in several foods including animal liver, some fortified breakfast cereals, and dietary supplements.Children: Vitamin A is likely safe when taken in the recommended amounts. The maximum amounts of vitamin A that are safe for children are based on age. Vitamin A is possibly unsafe for children when taken by mouth in high doses. Taking high doses can cause side effects, including irritability, sleepiness, diarrhea, and other problems.
Excessive use of alcohol: Drinking alcohol might increase vitamin A's potentially harmful effects on the liver.
Disorders in which the body does not absorb fat properly: People with conditions that affect fat absorption are not able to absorb vitamin A properly. These conditions include celiac disease, short gut syndrome, jaundice, cystic fibrosis, pancreatic disease, and cirrhosis of the liver. If you have one of these conditions, take water-soluble forms of vitamin A, called carotenoids, instead.
Iron deficiency: Iron deficiency might affect the body's ability to use vitamin A.
Liver disease: Too much vitamin A might make liver disease worse. Do not take vitamin A supplements if you have liver disease.
Malnutrition: In people with severe protein malnutrition, taking vitamin A supplements might result in having too much vitamin A in the body.
Zinc deficiency: Zinc deficiency might cause symptoms of vitamin A deficiency. Taking a combination of vitamin A and zinc supplements might be necessary to improve this condition.
Antibiotics (Tetracycline antibiotics)
Interaction Rating=Moderate Be cautious with this combination.
Vitamin A can interact with some antibiotics. Taking very large amounts of vitamin A along with some antibiotics can increase the chance of a serious side effect called intracranial hypertension. But taking normal doses of vitamin A along with tetracyclines doesn't seem to cause this problem. Do not take large amounts of vitamin A if you are taking antibiotics.
Some of these antibiotics include demeclocycline (Declomycin), minocycline (Minocin), and tetracycline (Achromycin).
Medications for skin conditions (Retinoids)
Interaction Rating=Major Do not take this combination.
Some medications for skin conditions have vitamin A effects. Taking vitamin A pills and these medications for skin conditions could cause too much vitamin A effects and side effects.
Medications that can harm the liver (Hepatotoxic drugs)
Interaction Rating=Moderate Be cautious with this combination.
Taking large amounts of vitamin A might harm the liver. Taking large amounts of vitamin A along with medications that might also harm the liver can increase the risk of liver damage. Do not take large amounts of vitamin A if you are taking a medication that can harm the liver.
Some medications that can harm the liver include acetaminophen (Tylenol and others), amiodarone (Cordarone), carbamazepine (Tegretol), isoniazid (INH), methotrexate (Rheumatrex), methyldopa (Aldomet), fluconazole (Diflucan), itraconazole (Sporanox), erythromycin (Erythrocin, Ilosone, others), phenytoin (Dilantin), lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), and many others.
Warfarin (Coumadin)
Interaction Rating=Moderate Be cautious with this combination.
Warfarin (Coumadin) is used to slow blood clotting. Large amounts of Vitamin A can also slow blood clotting. Taking Vitamin A along with warfarin (Coumadin) can increase the chances of bruising and bleeding. Be sure to have your blood checked regularly. The dose of your warfarin (Coumadin) might need to be changed.
Iron: Red blood cells need iron to make hemoglobin, the chemical that carries oxygen through the body. Taking vitamin A seems to improve hemoglobin levels in people who have low levels of iron and vitamin A.
There are no known interactions with foods.
Vitamin A is an important nutrient. It is found in many foods, including fruits, vegetables, eggs, whole milk, meat, and fish. The amount that should be consumed on a daily basis is called the recommended dietary allowance (RDA). The RDA is 900 mcg daily for males and 700 mcg daily for females. While pregnant, the RDA is 770 mcg daily. While breast-feeding, the RDA is 1300 mcg daily. In children, the RDA depends on age.
In supplements, vitamin A is available in two forms: pre-formed vitamin A (retinol or retinyl ester) and provitamin A (carotenoids). For products that contain both, only count the amount of pre-formed vitamin A to determine what is safe. Vitamin A is also available in many topical products, including creams, serums, and lotions. Speak with a healthcare provider to find out what type of product and dose might be best for a specific condition.
3-Dehydroretinol, 3-Déhydrorétinol, Acétate de Rétinol, Antixerophthalmic Vitamin, Axerophtholum, Dehydroretinol, Déhydrorétinol, Fat-Soluble Vitamin, Oleovitamin A, Palmitate de Rétinol, Retinoid, Retinoids, Rétinoïdes, Retinol, Rétinol, Retinol Acetate, Retinol Palmitate, Retinyl Acetate, Rétinyl Acétate, Retinyl Palmitate, Rétinyl Palmitate, Vitamin A Acetate, Vitamin A Palmitate, Vitamin A1, Vitamin A2, Vitamina A, Vitamine A, Vitamine A1, Vitamine A2, Vitamine Liposoluble, Vitaminum A.
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