Download vitamin A (vye-ta-min A) - DavisPlus

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Adverse Reactions/Side Effects
Misc: hypervitaminosis A syndrome.
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vitamin A (vye-ta-min A)
Aquasol A
Classification
Therapeutic: vitamins (fat-soluble)
Pregnancy Category A (oral), X (parenteral, or doses ⬎ RDA)
Indications
Treatment and prevention of deficiency states. Prevention of vitamin A deficiency in
patients who have fat malabsorption or are taking bile acid sequestrants.
Action
Serves as a cofactor in many biochemical processes. Necessary for growth, bone development, vision, reproduction, integrity of mucosal and epithelial surfaces, and
formation of visual pigment. Therapeutic Effects: Resolution of deficiency signs.
Prevention of deficiency.
Pharmacokinetics
Absorption: GI absorption requires bile acids, fat, lipase, and protein. Aqueous
preparations are absorbed more readily than emulsions.
Distribution: Stored primarily in the liver (2-yr supply); small amounts stored in
kidneys and lungs. Does not cross the placenta but enters breast milk.
Metabolism and Excretion: Mostly metabolized by the liver.
Half-life: Unknown.
TIME/ACTION PROFILE
ROUTE
ONSET
PEAK
DURATION
PO
IM
unknown
unknown
unknown
unknown
unknown
unknown
Contraindications/Precautions
Contraindicated in: Hypervitaminosis A; Malabsorption (oral products); Hypersensitivity to ingredients in preparations (chlorobutanol, polysorbate 80, butylated
hydroxyanisole, butylated hydroxytoluene).
Use Cautiously in: Lactation (supplements to infant necessary); Pregnancy
(avoid amounts greater than RDA); Severely impaired renal function.
⫽ Canadian drug name.
Plate # 0-Composite
⫽ Genetic Implication.
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Interactions
Drug-Drug: Cholestyramine, colestipol, and mineral oil decrease absorption
of vitamin A. Oral contraceptives increase plasma levels of vitamin A.
Route/Dosage
RE ⫽ retinol equivalents. Doses should be individualized on the basis of degree of
deficiency. RDA: Adult males 1000 mcg RE; adult females 800 mcg RE.
Kwashiorkor
IM (Children): 30 mg followed by oral dosing.
PO (Adults and Children ⬎8 yr): 10,000– 20,000/day for at least 2 mo.
PO (Children ⬍8 yr): 5,000– 10,000/day for at least 2 mo.
Xerophthalmia
PO, IM (Children): 110 mg/day PO as retinyl palmitate or 55 mg IM then 110 mg
PO/day given with vitamin E to improve effectiveness.
Parenteral dosing
IM (Adults): 1000,000 units/day for 3 days, then 50,000 units/day for 2 weeks with
additional followup oral therapy of 10,000– 20,000 units/day.
IM (Children 1– 8 yr): 17,500– 35,000 units/day for 10 days with additional followup oral therapy of 5000– 10,000 units/day.
IM (Infants): 7500– 15,000 units/day with additional followup oral therapy of
5000– 10,000 units/day.
IV (Adults and Children): Infused as part of TPN in amounts required to meet nutritional needs (in parenteral multivitamin preparations).
NURSING IMPLICATIONS
Assessment
● Assess patient for signs of vitamin A deficiency (night blindness; frequent eye, ear,
sinus, and GU infections; dry mucous membranes; rough, scaly skin with goose
pimple– like lesions; photophobia; and dry eyes) prior to and periodically
throughout therapy.
● Assess nutritional status through 24-hr diet recall. Determine frequency of consumption of vitamin A– rich foods.
CAPITALS indicate life-threatening, underlines indicate most frequent.
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● Lab Test Considerations: Chronic toxicity may cause increased blood glu-
cose, calcium, BUN, cholesterol, and triglyceride levels.
● Plasma vitamin A and carotene levels may be evaluated prior to therapy to determine vitamin A deficiency.
● With high doses, erythrocyte and leukocyte counts may be decreased, and erythrocyte sedimentation rate (ESR) and prothrombin time (PT) may be increased.
Potential Nursing Diagnoses
Imbalanced nutrition: less than body requirements (Indications)
Plate # 0-Composite
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quamation of skin and lips, hair loss, anorexia, vomiting, joint and bone pain). Instruct patient to report these symptoms promptly to health care professional.
● Advise patient that mineral oil may interfere with the absorption of fat-soluble vitamins and should not be used concurrently.
● Emphasize the importance of follow-up exams to evaluate progress. Ophthalmologic exams may be required prior to and periodically throughout therapy.
Evaluation/Desired Outcomes
● Prevention of or decrease in the symptoms of vitamin A deficiency.
Why was this drug prescribed for your patient?
Implementation
● PO: Administer with or after meals.
● Solution may be dropped directly into mouth or mixed with cereal, fruit juice, or
other food. Use calibrated dropper supplied by manufacturer to measure solution
accurately.
● IM: Parenteral administration is indicated only when oral administration is not
possible (because of malabsorption, NPO status, vomiting, or severe ocular damage).
● Do not administer vitamin A intravenously because of the risk of anaphylactic
shock and death.
Patient/Family Teaching
● Instruct patient to take medication as directed. If a dose is missed, it should be
omitted, as fat-soluble vitamins are stored in the body for long periods.
● Encourage patient to comply with diet recommendations of health care profes-
sional. Explain that the best source of vitamins is a well-balanced diet with foods
from the four basic food groups.
● Foods high in vitamin A include liver, fish liver oils, egg yolks, yellow-orange fruits
and vegetables, dark green leafy vegetables, whole milk, vitamin A– fortified skim
milk, butter, and margarine. Ordinary cooking does not destroy vitamin A, but frozen foods lose 5– 10% during storage for 12 mo.
● Patients self-medicating with vitamin supplements should be cautioned not to exceed RDA. The effectiveness of megadoses for treatment of various medical conditions is unproved, and this may cause side effects and toxicity.
● Review symptoms of hypervitaminosis A syndrome (headaches, bulging fontanelles in infants, irritability, yellow-orange discoloration of skin, drying and des䉷 2015 F.A. Davis Company
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