Description and Brand Names

Drug information provided by: Merative, Micromedex®

US Brand Name

  1. Alamast

Descriptions


Pemirolastis used to treat the itching in your eyes that happens with allergies.

Pemirolast works by preventing certain types of inflammatory cells from releasing irritating substances that cause allergic symptoms.

This medicine is available only with your doctor's prescription.

Before Using

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

This medicine has been tested in children 3 years of age and older and, in effective doses, has not been shown to cause different side effects or problems than it does in adults.

Geriatric

There is no specific information available comparing the use of pemirolast in the elderly with use in other age groups.

Breastfeeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Drug Interactions

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Contact lens–related irritation—Pemirolast should not be used to treat this condition

Proper Use

Pemirolast is used to help treat the itching that often occurs with allergic conjunctivitis.

  • To use the eye drops form of this medicine:
    • First, wash your hands. Then tilt the head back and, pressing your finger gently on the skin just beneath the lower eyelid, pull the lower eyelid away from the eye to make a space. Drop the medicine into this space. Let go of the eyelid and gently close the eyes. Blink a few times to make sure the eye is covered with the medicine.
    • To keep the medicine as germ-free as possible, do not touch the applicator tip to any surface (including the eye). Also, keep the container tightly closed. Serious damage to the eye and possible loss of vision may result from using contaminated eye drops.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

Use this medicine only as directed. Do not use more of it and do not use it more often than your doctor ordered.

  • For ophthalmic dosage form (eye drops):
    • For eye allergies:
      • Adults and children 3 years of age and older—Use one to two drops in each affected eye four times a day.
      • Children up to 3 years of age—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions

You should avoid wearing contact lenses when your eyes are red and irritated from your allergies.

For patients who continue to wear contact lenses and whose eyes are not red, be certain to wait at least 10 minutes after applying pemirolast to your eyes before replacing any contact lenses normally worn.

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

Less common

  1. Cough (mucus-producing)
  2. headache (severe)
  3. stomach pain and cramping
  4. pain and tenderness around eyes and cheekbones
  5. painful menstrual bleeding
  6. runny or stuffy nose
  7. tightness in chest
  8. troubled breathing

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  1. Chills
  2. cough
  3. fever
  4. sneezing
  5. sore throat

Less common

  1. Back pain
  2. burning feeling in eye
  3. eyelid swelling
  4. eye dryness
  5. foreign body feeling in eye
  6. general feeling of eye discomfort
  7. increased itching of the eye
  8. redness of the eye

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Portions of this document last updated: Feb. 01, 2024

Original article: https://www.mayoclinic.org/drugs-supplements/pemirolast-ophthalmic-route/description/drg-20065356