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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Limited Use [what does this mean?]
Generic drug name: fexofenadine (fex o FEN a deen)
Brand name(s): ALLEGRA, CHILDREN’S ALLEGRA
GENERIC: not available FAMILY: Antihistamines
Find the drug label by searching at DailyMed.

Limited Use [what does this mean?]
Generic drug name: loratadine (lor AT a deen)
Brand name(s): ALAVERT, CLARITIN, CLARITIN HIVES RELIEF
GENERIC: available FAMILY: Antihistamines
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

Fexofenadine caused decreased weight gain and survival in developing fetuses in animal studies. Use during pregnancy only for clear medical reasons. Tell your doctor if you are pregnant or thinking of becoming pregnant before you take these drugs.

Breast-feeding Warning

No information is available from either human or animal studies. It is likely that these drugs are excreted in human milk, and because of the potential for adverse effects in nursing infants, you should avoid these drugs while nursing.

Safety Warnings For This Drug [top]

Anticholinergic Effects

Warning: Special Mental and Physical Adverse Effects

Older adults are especially sensitive to the harmful anticholinergic effects of these drugs. Drugs in this family should not be used unless absolutely necessary.

Mental Effects: confusion, delirium, short-term memory problems, disorientation and impaired attention

Physical Effects: dry mouth, constipation, difficulty urinating (especially for a man with an enlarged prostate), blurred vision, decreased sweating with increased body temperature, sexual dysfunction and worsening of glaucoma

Non-Drug Approaches to Allergies

Avoid exposure to things that trigger your allergies or asthma, such as animals, bedding, chemicals, cosmetics, drugs, dust, mold, foods, pollens, or smoke. Wearing a mask reduces inhalation of drugs, pollens, and smoke. Many people with mildly red, itching eyes require no treatment. Cold compresses to the eyes may prove helpful. Using eye drops with vasoconstrictors whitens eyes for a while, but rebound redness can occur. Misuse of vasoconstrictors sets up a vicious cycle.

Facts About This Drug [top]

Fexofenadine is an antihistamine that is the metabolic breakdown product of the antihistamine terfenadine (SELDANE), which was removed from the market because it caused fatal heart rhythm disturbances. Fexofenadine does not appear to cause the fatal heart rhythm disturbances seen with terfenadine.[1]

Fexofenadine relieves symptoms of seasonal allergies such as sneezing, itchy, watery eyes, and red eyes but does not cure allergies. How this antihistamine compares with other antihistamines...

Fexofenadine is an antihistamine that is the metabolic breakdown product of the antihistamine terfenadine (SELDANE), which was removed from the market because it caused fatal heart rhythm disturbances. Fexofenadine does not appear to cause the fatal heart rhythm disturbances seen with terfenadine.[1]

Fexofenadine relieves symptoms of seasonal allergies such as sneezing, itchy, watery eyes, and red eyes but does not cure allergies. How this antihistamine compares with other antihistamines remains to be determined.[1]

Antihistamines are generally used to treat hives and itching, therefore an allergic reaction (rash and itching) to using these drugs orally may seem rare. There has been one case of urticaria (rash) reported following the use of fexofenadine. However, in a review of international reports, WHO (World Health Organization) Adverse Reactions database list 79 cases of urticaria associated with the use of fexofenadine.[2],[3]

Even though urticaria is a rare adverse effect, it is important to note that it can easily go unnoticed since it can mimic the underlying condition that the drug is being used to treat.

Loratadine is now sold as an over-the-counter. Loratadine is broken down in the body to desloratadine (CLARINEX). It relieves the symptoms of seasonal allergies and chronic itching but does not cure any condition. High doses increase the risk of adverse effects with loratadine. People with impaired kidney or liver function should only take 10 milligrams of the drug every other day. Older people may be more prone to adverse effects, such as dizziness and dry mouth. A dry mouth for a prolonged time can lead to dental problems.

Loratadine passes into the breast milk and should not be used when nursing. Do not use in the third trimester of pregnancy.

Before You Use This Drug [top]

Tell your doctor if you have or have had:

  • allergies to drugs
  • problems with urination
  • kidney problems
  • glaucoma
  • enlarged prostate
  • pregnancy or are breast-feeding

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • Do not drink alcohol or use other drugs that can cause drowsiness.
  • Until you know how you react to this drug, do not drive or perform other activities requiring alertness.
  • If you plan to have any surgery, including dental surgery, tell your doctor that you take this drug.
  • Protect yourself from sunburn, using a sunscreen or wearing protective clothing (loratadine).
  • Use sugarless gum, ice, or saliva substitutes if dry mouth develops.

How to Use This Drug [top]

  • If you miss a dose, take it as soon as you remember, but skip it if it is almost time for the next dose. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Take with food, water, or milk to avoid stomach upset.
  • Swallow extended-release forms whole.
  • Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Do not allow liquid form to freeze. Keep out of reach of children.

Interactions with Other Drugs [top]

The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:

AGENERASE, aluminum/magnesium antacids, amprenavir, NORVIR, ritonavir.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • cough
  • difficulty swallowing
  • dizziness
  • fast or irregular heartbeat
  • puffiness or swelling of eyelids or around eyes, face, lips, or tongue
  • shortness of breath
  • skin rash, hives, or itching
  • tightness in chest
  • wheezing
  • abdominal or stomach pain
  • clay-colored stools or dark urine
  • chills
  • diarrhea
  • headache
  • convulsions or seizures

Call your doctor if these symptoms continue:

  • confusion (loratadine)
  • dizziness
  • any change in vision (loratadine)
  • constipation
  • diarrhea
  • headache
  • dryness of mouth, nose, or throat (loratadine)
  • difficult or painful urination (loratadine)
  • nightmares (fexofenadine)
  • loss of appetite (loratadine)
  • increased appetite or weight gain (loratadine)
  • unusual excitement, nervousness, restlessness, or irritability
  • ringing or buzzing in ears (loratadine)
  • skin rash
  • stomach upset or pain
  • nausea (loratadine)
  • increased sweating (loratadine)
  • unusually fast heartbeat (loratadine)
  • increased sensitivity to the sun (loratadine)
  • drowsiness (loratadine)
  • clumsiness or unsteadiness
  • tremor
  • menstrual cycle change

Signs of overdose:

  • clumsiness or unsteadiness
  • severe dry mouth, nose, or throat
  • flushed or red face
  • shortness of breath
  • trouble breathing
  • fast or irregular heartbeat
  • severe drowsiness
  • seizures
  • hallucinations
  • trouble sleeping
  • faintness or lightheadedness

If you suspect an overdose, call this number to contact your poison control center: (800) 222-1222.

last reviewed February 28, 2021