Loratadine (loratadine)

In patients with chronic renal impairment (creatinine clearance of 30 mL/minute or less), both oral bioavailability and peak plasma concentrations of loratadine and desloratadine may be increased compared with individuals with normal renal function. However, elimination half-lives of the drug and its active metabolite appear to be similar to those of individuals with normal renal function. Patients with renal impairment receiving loratadine for self-medication should be advised to consult a clinician before initiating therapy, since a different dosage may be recommended. Therapy with loratadine conventional or orally disintegrating tablets or oral solution should be initiated at a dosage of 10 mg every other day in adults and children 6 years of age and older with a glomerular filtration rate less than 30 mL/minute and at a dosage of 5 mg every other day in children 2-5 years of age with renal insufficiency. In addition, therapy with the commercially available tablets containing loratadine in fixed combination with pseudoephedrine sulfate should be initiated in adults and children 12 years of age and older with a glomerular filtration rate less than 30 mL/minute at a dosage of 5 mg once daily when the 12-hour formulation is used or at a dosage of 10 mg every other day when the 24-hour formulation is used, since clearance of both loratadine and pseudoephedrine are decreased in such patients. Hemodialysis does not appear to affect the pharmacokinetics of loratadine or desloratadine.

The pharmacokinetics of loratadine and its active metabolite also may be altered in patients with hepatic impairment and dosage adjustment may be necessary. Therefore, patients with hepatic impairment receiving loratadine for self-medication should be advised to consult a clinician before initiating therapy, since a different dosage may be recommended. Therapy with loratadine conventional or orally disintegrating tablets or oral solution should be initiated at a dosage of 10 mg every other day in adults and children 6 years of age and older with hepatic failure and at a dosage of 5 mg every other day in children 2-5 years of age with hepatic failure. Since fixed-ratio combination preparations do not permit individual titration of dosages, and clearance of loratadine is decreased more substantially than that of pseudoephedrine sulfate in patients with hepatic impairment, the manufacturer recommends that tablets containing loratadine in fixed combination with pseudoephedrine sulfate generally not be used in such patients.

Loratadine is administered orally. Loratadine conventional tablets, orally disintegrating tablets, and the commercially available tablets containing the drug in fixed combination with pseudoephedrine sulfate can be administered without regard to meals.

Although the oral bioavailability of loratadine is increased when the drug is administered as the orally disintegrating tablet without water, the bioavailability of the active metabolite desloratadine (descarboethoxyloratadine) is unaffected, and the manufacturers state that the orally disintegrating tablets can be administered with or without water. The orally disintegrating tablets are administered by placing a tablet on the tongue, where it disintegrates within a few seconds, and then subsequently swallowing with or without water. Tablets containing loratadine in fixed combination with pseudoephedrine sulfate should be swallowed intact and patients should be instructed not to break, chew, or dissolve such tablets. Patients also should be instructed to take Claritin-D(R) 24 Hour extended-release tablets with a full glass of water.

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.

An increased incidence of hypospadias in male infants born to women who received loratadine during pregnancy was reported in one study. However, analysis of data from the National Birth Defects Prevention Study (NBDPS) indicated that use of loratadine during early pregnancy was not associated with an increased risk of second- or third-degree hypospadias. In addition, in 2 small prospective cohort studies that surveyed pregnant women who contacted a teratology information service, use of loratadine during the first trimester of pregnancy was not associated with major congenital anomalies and did not affect the rate of live birth, gestational age at birth, and birth weight. Despite these findings, it should be noted that interpretation of these results is limited by the statistical limitations of the studies (i.e., small sample size, inadequate power, reliance on patient recall of drug use, exclusion criteria). The 2 prospective cohort studies were powered to detect statistical significance only if a substantial (i.e., approximately threefold) increase in the overall rate of major congenital anomalies was observed; the study that relied on NBDPS data excluded first-degree hypospadias because of the difficulty of detecting this mildest form in routine surveillance, making it difficult to determine the relationship between loratadine and this form of hypospadias. Thus, while these data may be useful, further study is needed to completely rule out the teratogenic risk of loratadine. Because there are no adequate and controlled studies to date using loratadine in pregnant women, loratadine alone or in fixed combination with pseudoephedrine hydrochloride should be used during pregnancy only when the potential benefits justify the possible risks to the fetus. Reproduction studies in rats and rabbits using loratadine dosages up to 75 and 150 times, respectively, the maximum daily human dosage on a mg/m2 basis have not revealed evidence of harm to the fetus.

Loratadine and desloratadine distribute readily into breast milk, achieving concentrations that are equivalent to those in plasma (i.e., a milk to plasma AUC ratio of 1.17 and 0.85, respectively). The manufacturer states that about 0.03% of a single 40-mg dose of loratadine was distributed into breast milk as loratadine and desloratadine over 48 hours. Pseudoephedrine also distributes readily into breast milk. Caution should be exercised when loratadine is administered alone or in fixed combination with pseudoephedrine to a nursing woman, and a decision should be made whether to discontinue nursing or the drug, taking into account the importance of the drug to the woman.

No enhanced messaging available.