Children's Allergy (diphenhydramine HCl)

Dosage should be individualized according to the patient's response and tolerance.

Diphenhydramine hydrochloride usually is administered orally.

Diphenhydramine citrate usually is administered orally.

When oral therapy is not feasible, diphenhydramine hydrochloride may be given by deep IM or, preferably, IV injection. The drug should not be given subcutaneously, intradermally, or perivascularly because of its irritating effects; local necrosis has been reported following subcutaneous or intradermal administration of parenteral diphenhydramine. IV use of the drug in a home-care setting should be employed under careful supervision. Use of diphenhydramine for local anesthesia via local infiltration is discouraged because of the risk of local tissue necrosis. Diphenhydramine hydrochloride should not be given to premature or full-term neonates. (See Cautions: Pediatric Precautions.)

For the temporary relief of pruritus associated with various skin conditions and disorders, diphenhydramine hydrochloride-containing preparations are applied topically in the form of a cream, lotion, or topical solution. The possibility of clinically important percutaneous absorption of the drug following topical application should be considered. (See Cautions.)

There is no enhanced messaging for this drug.

There are no contraindication interactions for this drug.

Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

Agents That Affect Iodide/Radioactive Iodide

SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

MECHANISM OF ACTION: Many compounds can affect iodide protein binding and alter iodide pharmacokinetics and pharmacodynamics.(1)

CLINICAL EFFECTS: Compounds that affect iodide pharmacokinetics and pharmacodynamics may impact the effectiveness of radioactive iodide.(1)

PREDISPOSING FACTORS: Compounds that affect iodide pharmacokinetics and pharmacodynamics are expected to have the most impact during therapy using radioactive iodide. Diagnostic procedures would be expected to be impacted less.

PATIENT MANAGEMENT: Discuss the use of agents that affect iodide pharmacokinetics and pharmacodynamics with the patient's oncologist.(1) Because indocyanine green contains sodium iodide, the iodine-binding capacity of thyroid tissue may be reduced for at least one week following administration. Do not perform radioactive iodine uptake studies for at least one week following administration of indocyanine green.(2) The manufacturer of iopamidol states administration may interfere with thyroid uptake of radioactive iodine and decrease therapeutic and diagnostic efficacy. Avoid thyroid therapy or testing for up to 6 weeks post administration of iopamidol.(3)

DISCUSSION: Many agents interact with radioactive iodine. The average duration of effect is: anticoagulants - 1 week antihistamines - 1 week anti-thyroid drugs, e.g: carbimazole, methimazole, propylthiouracil - 3-5 days corticosteroids - 1 week iodide-containing medications, e.g: amiodarone - 1-6 months expectorants - 2 weeks Lugol solution - 3 weeks saturated solution of potassium iodine - 3 weeks vitamins - 10-14 days iodide-containing X-ray contrast agents - up to 1 year lithium - 4 weeks phenylbutazone - 1-2 weeks sulfonamides - 1 week thyroid hormones (natural or synthetic), e.g.: thyroxine - 4 weeks tri-iodothyronine - 2 weeks tolbutamide - 1 week topical iodide - 1-9 months (1)

Agents That Affect Iodide/Sodium Iodide I 131

SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

MECHANISM OF ACTION: Many compounds can affect iodide protein binding and alter iodide pharmacokinetics and pharmacodynamics.(1,2)

CLINICAL EFFECTS: Compounds that affect iodide pharmacokinetics and pharmacodynamics may impact the effectiveness of radioactive iodide.(1,2)

PREDISPOSING FACTORS: Compounds that affect iodide pharmacokinetics and pharmacodynamics are expected to have the most impact during therapy using radioactive iodide. Diagnostic procedures would be expected to be impacted less.

PATIENT MANAGEMENT: Discuss the use of agents that affect iodide pharmacokinetics and pharmacodynamics with the patient's oncologist.(1,2) Because indocyanine green contains sodium iodide, the iodine-binding capacity of thyroid tissue may be reduced for at least one week following administration. Do not perform radioactive iodine uptake studies for at least one week following administration of indocyanine green.(3) The manufacturer of iopamidol states administration may interfere with thyroid uptake of radioactive iodine and decrease therapeutic and diagnostic efficacy. Avoid thyroid therapy or testing for up to 6 weeks post administration of iopamidol.(4)

DISCUSSION: Many agents interact with radioactive iodine. The average duration of effect is: anticoagulants - 1 week antihistamines - 1 week anti-thyroid drugs, e.g: carbimazole, methimazole, propylthiouracil - 3-5 days corticosteroids - 1 week iodide-containing medications, e.g: amiodarone - 1-6 months expectorants - 2 weeks Lugol solution - 3 weeks saturated solution of potassium iodine - 3 weeks vitamins - 10-14 days iodide-containing X-ray contrast agents - up to 1 year lithium - 4 weeks phenylbutazone - 1-2 weeks sulfonamides - 1 week thyroid hormones (natural or synthetic), e.g.: thyroxine - 4 weeks tri-iodothyronine - 2 weeks tolbutamide - 1 week topical iodide - 1-9 months (1,2)

There are no moderate interactions for this drug.

There is no enhanced messaging for this drug.

There are no contraindication contraindications for this drug.

There are no severe contraindications for this drug.

• Disease of liver
• Hepatic failure
• Renal disease with moderate to severe function impairment

There is no enhanced messaging for this drug.

Rare or Very Rare

• Abnormal hepatic function tests
• Anaphylaxis
• Angioedema

More Frequent

• Headache disorder

Less Frequent

• Acute abdominal pain
• Conjunctivitis
• Drowsy

Rare or Very Rare

• Acute cognitive impairment
• Alopecia
• Anticholinergic toxicity
• Blurred vision
• Bronchitis
• Concentration difficulty
• Cough
• Dizziness
• Dream disorder
• Dry nose
• Dry throat
• Dyspnea
• Earache
• Epistaxis
• Fatigue
• Gastritis
• Hyperhidrosis
• Hyperkinesis
• Increased appetite
• Insomnia
• Malaise
• Nausea
• Nervousness
• Palpitations
• Pharyngitis
• Sedation
• Skin photosensitivity
• Skin rash
• Tachycardia
• Tinnitus
• Urinary incontinence
• Urinary retention
• Visual changes
• Voice change
• Weight gain
• Xerostomia

No enhanced messaging available.

No enhanced messaging available.

Reproduction studies in rats and rabbits receiving diphenhydramine hydrochloride dosages up to 5 times the recommended human dosage have not revealed evidence of harm to the fetus. However, diphenhydramine has been shown to cross the placenta. In one epidemiologic study, use of bromodiphenhydramine (no longer commercially available) but not diphenhydramine was associated with an increased risk of teratogenic effects. In another epidemiologic study, there also was no evidence of increased risk of teratogenicity associated with diphenhydramine use during the first trimester, although a modest association could not be ruled out. Use of diphenhydramine during the first trimester of pregnancy has been associated with an increased risk of cleft palate alone or combined with other fetal abnormalities, and the drug has been reported to potentiate the teratogenic effect of morphine in mice. The manufacturers state that there are no adequate and controlled studies to date using diphenhydramine in pregnant women, and the drugs should be used during pregnancy only when clearly needed.

Diphenhydramine has been detected in milk. Because of the potential for serious adverse reactions to antihistamines in nursing infants, a decision should be made whether to discontinue nursing or diphenhydramine, taking into account the importance of the drug to the woman.

No enhanced messaging available.