Grastek
Grastek contains timothy grass pollen allergen extract. It's a type of allergen immunotherapy that helps treat allergy symptoms caused by Timothy grass pollen. Grastek is FDA approved for people between ages 5 and 65 years old. It's a sublingual tablet that's dissolved under the tongue once a day. Possible side effects include itchy mouth, throat irritation, and swelling in the mouth.
What is Grastek?
What is Grastek used for?
- Allergic rhinitis (seasonal allergy) caused by grass pollen
How Grastek works
Grastek is an allergen immunotherapy. It's an allergen extract that comes from Timothy grass (common in pastures and on the roadside).
The way Grastek works isn't fully known. But it's thought to help treat allergies to grass pollen by changing how your immune system reacts to Timothy grass pollen.
Drug facts
| Common Brands | Grastek |
|---|---|
| Drug Class | Allergen extract |
| Controlled Substance Classification | Not a controlled medication |
| Generic Status | No lower-cost generic available |
| Availability | Prescription only |
Side effects of Grastek
The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Common Side Effects
Adults:
- Itchy mouth (27%)
- Throat irritation (23%)
- Itchy ear (13%)
- Swelling in the mouth (11%)
- Tingling in the mouth (10%)
- Itchy tongue (6%)
Children:
- Itchy mouth (24%)
- Throat irritation (21%)
- Swelling in the mouth (10%)
- Itchy tongue (9%)
- Itchy ear (7%)
- Swollen lip (7%)
- Tingling in the mouth (5%)
- Mouth redness (5%)
Less Common Side Effects
- Mouth or throat redness
- Throat pain
- Numbness in the mouth
- Swollen lip
- Swollen tongue
- Swollen throat
- Trouble swallowing
- Headache
- Nausea
- Chest discomfort
- Hives
Grastek serious side effects
Contact your healthcare provider immediately if you experience any of the following.
- Serious allergic reaction: trouble breathing, throat swelling or tightness, chest tightness, swelling of the lips or tongue, dizziness, fainting, fast heartbeat, hives, itchy skin, flushing, stomach pain, nausea, vomiting
The following Grastek side effects have also been reported
Side effects that you should report to your care team as soon as possible:
- Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
- Heartburn, pain or trouble swallowing, chest pain that does not go away or gets worse
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
- Burning or tingling of the tongue, mouth, throat, or face
- Irritation inside the mouth or throat
- Itching of the mouth, lips, tongue, or ears
- Mild swelling of the mouth, lips, tongue, or throat
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Pros and cons of Grastek
Pros
- Dissolves under the tongue, so it's easy to take
- Improves symptoms during grass pollen allergy season for people as young as 5 years old
- Only need to take once a day
- Can take it for 3 years in a row and still get relief during the grass pollen season the year after you stop
Cons
- Need to start taking the medication 3 months before grass pollen season for it to work best
- Risk of severe, life-threatening allergic reactions
- Not recommended if you or your child can't or don't want to use an epinephrine autoinjector (EpiPen) in case of a severe allergic reaction
- Can't swallow for 1 minute and can't eat or drink for 5 minutes after taking
Pharmacist tips for Grastek
- You'll need to take the first dose of Grastek at the prescriber's office and stay for at least 30 minutes. The care team will check for signs of an allergic reaction, like trouble breathing, throat swelling, rash, and a fast heartbeat. If you don't have a bad reaction, you can take the medication at home after that.
- Make sure you have an epinephrine autoinjector like EpiPen ready and you know how to use it. This is important in case you have an allergic reaction to Grastek. If an allergic reaction happens, inject epinephrine into the thigh and get emergency medical help right away.
- Always supervise your child when they take Grastek. Keep a close eye for signs of allergic reaction. Give them epinephrine and call 911 right away if they have an allergic reaction after taking this medication.
- Let the care team know if you have any side effects after taking Grastek that bother you or get worse. This can include an itchy, swollen, or tingly mouth; throat irritation; or a swollen throat or tongue.
- Tell your healthcare professionals that you're taking Grastek. There are some medications that can affect how well emergency treatments that you might need while taking Grastek work. For example, beta blockers can stop epinephrine and rescue inhalers from working well.
- It's not recommended to take more than one allergen immunotherapy at the same time. This might raise your risk for severe allergic reactions.
- Store Grastek tablets at room temperature sealed in the original packaging. Keep them away from moisture so the tablets don't melt.
How to take Grastek:
- Take the Grastek tablet out from the package only when you're ready for your dose. This helps protect the tablets from moisture in the air.
- Make sure you use clean, dry hands to remove the Grastek tablet from the foil packaging. If your hands are wet, the tablet can start to dissolve in your hands and you might not get the full dose of medication.
- Place 1 Grastek tablet under the tongue right after you take it out of the package. Keep the tablet under the tongue until it dissolves all the way. Don't take the medication with any food or drinks.
- Once the Grastek tablet fully dissolves, don't swallow for at least 1 minute. And avoid eating and drinking for 5 minutes after the tablet dissolves. This helps make sure all the medication get absorbed from under your tongue.
- Wash your hands after you take Grastek. There might be powder or residue from the tablet on your hands.
Risks and warnings for Grastek
Grastek can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Severe allergic reactions
- Risk factors: History of severe allergic reaction
Grastek can cause severe, life-threatening allergic reactions like anaphylaxis. It might not be safe for you if you have medical problems that could make it less likely for you to survive an allergic reaction. This could be lung problems, uncontrolled asthma, or a recent heart attack. It also might not be right for you if you take medications that could affect how emergency treatments work, like beta blockers. Talk to your prescriber to see if Grastek is safe for you.
Because of the risk of a serious allergic reaction, you have to take your first dose of Grastek at the medical office. You'll need to stay there for at least 30 minutes so the healthcare team can watch for any signs of an allergic reaction. This helps make sure it's safe for you to take it at home.
You'll get prescribed an epinephrine autoinjector like an EpiPen. Your care team will teach you how to use it if you have an allergic reaction at home. Look out for signs of an allergic reaction like trouble breathing, chest tightness, or swelling of your lips or tongue. If this happens, inject epinephrine into your thigh muscle and call 911 right away.
Difficulty breathing
- Risk factors: Asthma
Grastek can cause side effects in the mouth and throat that can make it harder for you to breathe. They can include swelling of the tongue or throat. Stop taking Grastek and call your prescriber if you have side effects that make it hard to breathe. Also stop taking the medication and get medical help if you're having an asthma attack because it could make breathing even harder.
Trouble swallowing (eosinophilic esophagitis)
Although it's rare, some people taking allergen immunotherapy that dissolves under the tongue developed eosinophilic esophagitis. This happens when the immune system attacks the esophagus (the tube that connects your mouth to your stomach). It can cause stomach pain, pain while eating, and trouble eating or drinking. If you have these symptoms, stop taking Grastek and call your healthcare team so they can check it out.
Swelling and irritation in the mouth
Grastek can cause mouth irritation as a side effect. If you have mouth ulcers, sores, or thrush (a yeast infection in your mouth), tell your prescriber. Also let them know if you've had any recent surgery in the mouth. Your prescriber will probably tell you to stop taking Grastek until your mouth completely heals. The side effects of the medication can make irritation worse and slow down healing.
Grastek dosage
Dose pack| Dosage | Quantity | Price as low as | Price per unit |
|---|---|---|---|
| 30 sublingual tablets of 2800 BAU | 1 dose pack | $287.75 | $287.75 |
Typical dosage for Grastek
The typical dose is 1 Grastek tablet dissolved under the tongue once a day. Each tablet contains 2,800 bioequivalent allergy units (BAU).
You need to take your first dose at a medical office so that you're supervised by a healthcare professional. They have to make sure that the medication is safe for you before you can start taking it at home.
You usually start taking Grastek at least 3 months before allergy season and keep taking it during the season.
For lasting effects, you can also take Grastek every day for 3 years in a row (including between seasons). After you finish the 3-year treatment, the effects of the medication can last for another year.
How much does Grastek cost?
$287.75
Grastek contraindications
Contraindications are specific health conditions or situations in which a person should not take a medication due to safety concerns. If you have any of the following conditions or if any of the following apply to you, let your healthcare provider know because Grastek will not be safe for you to take.
- Severe, unstable, or uncontrolled asthma
- History of any severe allergic reaction
- History of any severe reaction around the mouth or throat after taking other allergen immunotherapy dissolved under the tongue
- History of eosinophilic esophagitis (a condition where your body's immune system attacks the tube connecting your mouth to your stomach)
- Allergy to gelatin
