vitamins Flashcards
thiamine
disease: wet and dry beriberi
cause: alcohol intake and furosemide which increase urniary loss of thaimine,
symptoms: weakness, nerve degeneration, irritability, poor arm and leg cordination, edema, large heart heart failure, poor gluocse metabolism, depression and weakness and after 10 days
treatment: thiamine supplemnets , multivitamins,
VITAMIN B2
riboflavin: for migraine and lactic acidosis after antiretroviral therpy.
disease: ariboflavinosis
symptoms: glossitis, cheilosis, seborrehic dermatitis, stomatitis, eye disorder, throat disorder, nervous system disorder.
cause: alcohol and some drug
treatment: riboflavin in form of tabelt and capsule, consitituent of multivitamin
VITAMIN B2
drugs that cause deficiency
beritutrate, oral contraceptives:
phenothiazine, trycyclic antidepressent,
probenecid, reduce GI absorption and increase urniary excertion.
Vitamin b3
Niacin, niacinamide
Two enzymes:
(NAD): nicotinamide adenine dinucleotide —> hydrogen and electron acceptor
(NADP): nicotinamide adenine di nucleotide phosphate: H+ and e- donor
Both work as metbolism of carbs, fats and protien, rhodopsin synthesis, cellular respiration
Deficiencie: pallagra
Vitamin b5
Pantothenic acid
From greek word means everywhere,
Deficiency is rare
Useful in: acne, allergies, alopecia, aging, arthritis, asthma, burning feet, Parkinson syndrome, grey hair, dandruff, low cholesterol and increased exercise performance.
Vitamin B6 (Pyridoxine)
- It occurs in food as pyridoxine, pyridoxal and pyridoxamine.
cause:Drugs: hydralazine, Isoniazid, Penicillamine.
B6 deficiency anemia and / or peripheral neuritis by acting as pyridoxine antagonist.
Signs and Symptoms Depression. Vomiting.Skin disorders.Nerve irritation. Impaired immune system.
Toxicity Potential: Irreversible nerve damage with > 200 mg/day (RDA ≤ 2 mg/D) (Nerve damage. - Difficulty walking.
- Numbness in hands & feet.)
Vitamin B7 (Biotin / Vitamin H)
cause: Avidin in raw egg white.forming complex with biotin (biotin – avidin) prevents absorption of biotin.
Signs and Symptoms:
Scaly inflamed skin, tongue, and lip changes
* Poor appetite, nausea, vomiting
* Anemia
* Muscle pain and weakness
* Poor growth
Vitamin B9 (Folic acid)
uses: Prevention of occurrence of neural tube defects of fetus (during pregnancy)
* Prevention of mucosal & GI side effects secondary to methotrexate use.
Causes: Drugs: methotrexate, Sulfasalazine.
symptoms: anemia (Megaloblastic, Macrocytic )
* RBC grow, cannot divide
* Megaloblast: large, immature RBC
* Looks like vit. B12 deficiency (but no neurological involvement)
Neural Tube Defects:
Neural tube closes first 28 days of pregnancy and brain, and spinal cord are formed.
* By the time pregnancy is confirmed, damage have occurred.
* Folic acid deficiency during pregnancy causes spinal cord defects.
Two major defects:
- Spins bifida.
- Anencephaly.
Vitamin B12 (Cobalamins)
Available in 2 forms: Cyanocobalamin & Methyl cobalamin.
Synthesized by microorganisms in animals
condition: pernicious anemia (megaloblastic, macrocytic anemia)
Causes: decrease absoption. due to ppi, h2ra and metformin, AG,
symptoms: Nerve degeneration, weakness, Tingling / numbness / parasthesia in the extremities, Paralysis and death, Looks like folate deficiency, Take long years (up to 20) on a deficient diet to see nerve damage.
Treatment B12 injection, Anemia can be corrected with large doses of folate but the neuropathies cannot.
Vitamin A:
Forms?
Sources ?
Transport and Metabolism?
forms of Vitamin A:
Retinol: Found in animal sources, retinol is often esterified with fatty acids, typically as retinyl palmitate.
Retinal: crucial role in vision by functioning in the retina.
Retinoic Acid: for gene expression regulation and cell development.
sources: animal: Provide vitamin A primarily in the form of retinol.
plant: Provide provitamin A carotenoids, such as β-carotene
Transport: Vitamin A is transported in the blood by retinol-binding protein (RBP), which is synthesized in the liver.
Metabolism: Carotenoids like β-carotene are absorbed by intestinal cells and converted into retinal, then to retinol and retinoic acid. This conversion can also occur in the liver.
Vitamin A:
Provitamin A Carotenoids:
β-Carotene: The most common provitamin A carotenoid found in plants. A large carrot, containing approximately 15 mg of β-carotene, can meet the daily vitamin A requirement.
Lycopene: A red pigment in tomatoes, lycopene is a potent antioxidant that can reduce the risk of prostate cancer and cataracts.
Lutein and Zeaxanthin: Yellow pigments found in leafy vegetables.
Causes of Vitamin A Deficiency:
Drug Interactions: Oral contraceptives, methotrexate, Al3+-containing antacids, cortisone, very high levels of vitamin E, (e.g. cholestyramine).
Cases: chronic diarrhea, cystic fibrosis, and kidney or liver disease.
mineral oil decrease the absorption
Cancer Treatments
Chronic Illness or Post-Surgery Recovery
Alcohol, smoking and caffeine.
Signs, Symptoms, and Complications of Vitamin A Deficiency:
Night blindness
Xerosis: mucus-secreting cells are replaced by keratin producing cells
Xerophthalmia: dry eye.
Dry skin
Impaired Immunity: leading to frequent infections (especially RTI)
vitamin A
toxicity
Most cases of vitamin A overdose occur from supplements
* Infants and children are more susceptible
* Vitamin A is a teratogen and high doses (˃ 1 mg retinol) may produce birth defects, even with
exposure for 1 week in early pregnancy.Pregnant women should avoid excess intake of vitamin A.
Retinol is most dangerous form in pregnancy & its daily dose should not exceed 2.5 mg
