Pharmacologic Profile

General Use

Used in the prevention and treatment of vitamin deficiencies and as supplements in various metabolic disorders.

General Action and Information

Serve as components of enzyme systems that catalyze numerous varied metabolic reactions. Necessary for homeostasis. Water-soluble vitamins (B-vitamins and vitamin C) rarely cause toxicity. Fat-soluble vitamins (vitamins D and E) may accumulate and cause toxicity.

Contraindications

Hypersensitivity to additives, preservatives, or colorants.

Precautions

Dose should be adjusted to avoid toxicity, especially for fat-soluble vitamins.

Interactions

Pyridoxine in large amounts may interfere with the effectiveness of levodopa. Cholestyramine, colestipol, and mineral oil ↓ absorption of fat-soluble vitamins.

Nursing Implications

Assessment

• Assess patient for signs of vitamin deficiency before and periodically throughout therapy.
• Assess nutritional status through 24-hr diet recall. Determine frequency of consumption of vitamin-rich foods.

Potential Nursing Diagnoses

• Imbalanced nutrition: less than body requirements (Indications)
• Deficient knowledge related to disease processes and medication regimen (Patient/Family Teaching)

Implementation

• Because of infrequency of single vitamin deficiencies, combinations are commonly administered.

Patient/Family Teaching

• Encourage patients to comply with diet recommendations of physician or other health care professional. Explain that the best source of vitamins is a well-balanced diet with foods from the four basic food groups.
• Patients self-medicating with vitamin supplements should be cautioned not to exceed RDAs. The effectiveness of megadoses for treatment of various medical conditions is unproved and may cause side effects and toxicity.

Evaluation/Desired Outcomes

• Prevention of, or decrease in, the symptoms of vitamin deficiencies.