Lesson 4 Antihistamines

Text: Antihistamines

Grammar: The Absolute Participle Complex

I. Active Vocabulary

allergy antihistamine to counteract itching runny nose pollen ragweed mast cell to swell stuffy nose rash hives hay fever decongestant drowsiness restlessness moodiness blurred vision confusion difficulty urinating glaucoma

['xlqGI] ["xntI'hIstqmJn] ["kaVntq'xkt] ['ICIN] ['rAnI"nqVz] ['pPlqn] ['rxgwJd] ['mRst"sel] [swel] ['stAfI"nqVz] [rxS] [haIvz] ['heI"fJvq] ["dJkqn'Gestqnt] ['draVzInIs] ['restlqsnIs] ['mHdInIs] ['blE:d 'vIZn] [kqn'fjHZn] ['jVrIneItIN] [glL'kqVmq]

алергія антигістамін протидіяти, нейтралізувати що свербить ринорея (виділення водянистого слизу з носа) пилок амброзія мастоцит набрякати закладений ніс висип кропив’янка поліноз, сінна гарячка, сезонний алергічни риніт протизастійний, протинабряковий засіб сонливість невгамовність, занепокоєність різка зміна настрою розфокусований зір втрата орієнтації утруднене сечовипускання глаукома

II. Read the following text. Antihistamines

A n antihistamine is a type of drug used to fight allergic reactions. It encompasses a broad class of drugs that can treat conditions ranging from minor to life threatening. Different antihistamines are used for different types of reactions. However, at their root, all antihistamines do the same thing – they counteract a type of chemical released by the body immune system, known as histamine.

Antihistamines work by targeting the immune system response that leads to allergy symptoms such as itching and a runny nose. When a body comes into contact with whatever an allergic trigger may be (whether it is pollen, ragweed, or another substance), mast cells of the immune system produce substances called histamines, which act on receptors in the nose and throat. That’s what causes the tissue in the nose to swell (producing a stuffy nose), the nose and eyes to run, and the eyes to itch. Sometimes this allergic reaction also triggers an itchy rash on the skin, called hives. Antihistamines reduce or block the action of histamines by preventing them from attaching to their receptors.

Antihistamines are effective at reducing symptoms of different types of allergies, including seasonal allergies (hay fever) and food allergies, but they can’t relieve every symptom. To help treat nasal congestion, a doctor may recommend adding a decongestant (some drugs combine an antihistamine and decongestant).

Antihistamines come in different forms, including tablets, capsules, liquids, nasal sprays, and eyedrops. Some antihistamines are only available by prescription; others you can buy over the counter (OTC) at your local pharmacy or supermarket.

Examples of prescription antihistamines include: desloratadine (Clarinex), levocetirizine (Xyzal), carbinoxamine (Palgic), cyproheptadine (generic only), hydroxyzine (Atarax, Vistaril), azelastine (Astelin, Astepro nasal sprays), emadastine (Emadine eyedrops), azelastine (Optivar eyedrops), levocabastine (Livostin eyedrops). Examples of OTC antihistamines include: diphenhydramine (Benadryl), fexofenadine (Allegra), loratadine (Claritin, Alavert), chlorpheniramine (Chlor-Trimeton), brompheniramine (Dimetane), cetirizine (Zyrtec), clemastine (Tavist). Allergy eyedrops such as Emadine and Livostin can help specifically with symptoms of eye allergies, including itchy, watery eyes. Some medications contain a combination of an antihistamine and a decongestant to relieve congestion. An example is Claritin-D, which combines the antihistamine Claritin with the decongestant pseudoephedrine.

Like just about all drugs, antihistamines can cause side effects, and some antihistamines cause more side effects than others. Drugs such as Chlor-Trimeton, Tavist, and Benadryl belong to an older group of antihistamines known as “first-generation” antihistamines. They tend to cause more side effects, particularly drowsiness. Newer-generation prescription antihistamines such as Clarinex, Zyrtec, and Allegra have fewer side effects, so they may be a better choice for some people.

Some of the main side effects of antihistamines include: dry mouth, drowsiness, dizziness, nausea and vomiting, restlessness or moodiness (in some children), difficulty urinating or inability to urinate, blurred vision confusion

When using antihistamines, follow these precautions:

• If you’re taking an antihistamine that causes drowsiness, try to take it before bedtime. Avoid using during the day when driving or operating heavy machinery.

• Before taking antihistamines, go over all of your medications with your doctor or pharmacist. Antihistamines may interact with other medications you are taking.

• Talk to your doctor before using antihistamines if you have an enlarged prostate, heart disease, high blood pressure, thyroid problems, kidney or liver disease, a bladder obstruction, or glaucoma or other conditions that cause a rise in eye pressure. Also check with your doctor if you are pregnant or nursing.

Answer the following questions on the text.

1. What type of drug is an antihistamine?

2. How do histamines work?

3. What causes the tissues in the nose to swell?

4. Can you name any allergens? What are they?

5. What forms of histamines are there?

6. Why do some medications contain a combination of an antihistamine and a decongestant?

7. What antihistamines produce more severe side effects?

8. It is necessary to take it before bedtime, isn’t it?

9. Why is it required to go over all of your medications with your doctor or pharmacist before taking antihistamines?

10. Is it safe to take antihistamines by pregnant women or nursing mothers?