This medication is used to treat allergy to house dust mites. It contains an extract made from certain house dust mites. Before prescribing this medication, your doctor must do lab/medical tests (such as skin or blood tests) to learn what you are allergic to. This allergen extract works by making your body less sensitive to the house dust mites that cause your allergies. This medication will not work right away to relieve allergy symptoms. When taken as directed, it may help relieve symptoms such as sneezing, runny/stuffy nose, cough, or itchy/watery eyes that are caused by allergies.

Read the Medication Guide provided by your pharmacist before you start taking this medication and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth without food as directed by your doctor, usually once daily. With dry hands, remove one tablet from the package just before taking. Place the tablet under the tongue and allow it to dissolve (usually within 10 seconds). Do not swallow for at least 1 minute after taking this medication. Do not chew or swallow the tablet. Do not eat or drink while the tablet is dissolving in your mouth and for 5 minutes after taking it. Wash your hands after handling the tablet.

Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day.

Tell your doctor if your condition does not get better or if it gets worse.

Mild mouth/eye/ear/throat itching, throat dryness/irritation, or mouth/tongue/lip swelling may occur, especially during the first few days of treatment. Nausea, mouth blisters, or changes in how food tastes may also occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Get medical help right away if you have any very serious side effects, including:

• throat tightness/swelling
• trouble swallowing/breathing
• voice changes (such as hoarse voice, trouble speaking)
• chest pain

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction (see also Warning section).

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

See also Warning section.

Before taking this medication, tell your doctor or pharmacist if you are allergic to it; or to other allergen extracts; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• breathing disorders (such as asthma, chronic obstructive pulmonary disease-COPD)
• heart problems (such as angina, irregular heartbeat, previous heart attack)
• mouth irritation (such as cold sore, ulcer, infection)
• a certain esophagus problem (eosinophilic esophagitis)
• previous allergic reaction
• other current allergy treatments (such as allergy shots, other allergen extracts)

Before having surgery or a dental procedure (such as tooth extraction), tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products). Your doctor or dentist may direct you to briefly stop treatment with this medication after surgery or a procedure. Ask your doctor or dentist for details.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is unknown if this medication passes into breast milk. Consult your doctor before breastfeeding.

See also Warning section.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others. It may harm them, even if their symptoms are the same as yours.

Your doctor may direct you to also use other medications (such as antihistamines, nasal sprays for allergies) for allergy symptoms or for mild side effects. Ask your doctor for details.

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.