Tablets and Tablet Making

The tablet is the most common form of medication¹ for the administering of a drug in a dry state.

A great variety of shapes and sizes is available among medicinal tablets. The most common shape is a circular body with flat or slightly convex sides. There can also be rectangular, triangular and other shapes in the case of specialty tablets².

The preliminary consideration in selection of particular shapes and sizes is essentially ethical. The dimensions should be chosen so that tablets prepared would have a pleasing appearance. Similarly, the use of a tablet is also an important consideration. A tablet meant for making solutions must dissolve as quickly as possible and so it should be as thin as possible. This will require a larger diameter than average tablets of the same weight. Tablets, which are to be dissolved slowly in the mouth, should be flat for convenience of the user and thick enough to have a lasting effect on which the efficiency of the tablet will depend. Tablets which are to be coated after compression, must have a deep convex shape³ and be harder than other tablets.

In addition to the above considerations, there can also be important technical reasons, which may influence the selection of particular dimensions. The density and compression ratio (the extent to which a powder can be compressed) are important factors.

From a purely physical point of view, the technique of tablet making (tabletting) may he defined as a process whereby a known volume of a drug in a finely divided state is subjected to pressure in a die between two punches.

Tablets can be easily made from such drugs as sodium chloride and other alkali halides⁴, even without any auxiliary substances. For some other drugs, like lactose, the addition of auxiliary substances may be necessary to prevent binding or sticking in the tablet machine.

The extent of pressure plays a very important part during tabletting. Tablets, which are to dissolve in the mouth, must be more strongly compressed than other tablets for internal administration. At the same time higher pressure causes an increase in friction, which necessitates the use of greater amounts of lubricants and glidants⁵. Glidants (e.g. natural starch) are added to the tablet material to improve its flow properties. Lubricants are substances, which facilitate smooth ejection of tablets after compression.

Notes

1. the most common form of medication – найбільш поширена форма лікарських препаратів.

2. specialty tablets – таблетки спеціального призначення

3. deep convex shape – дуже випукла форма

4. alkali halides – лужні галоїдні сполуки або галогеніди

5. lubricants and glidants – змащувальні речовини і речовини, що надають ковзких властивостей.

Exercises

Ex.1. a) What meaning do the following prefixes add?

Pre -war, pos twar, intra venous, inter costal, over cook, under cook, anti -abortion, pro -abortion, re use, sub marine, co -author, bi lingual.

b)Find the prefixes, translate the words with and without them:

Antiwar, subdivide, co-operate, overload, pro-reform, post-graduate, rewrite, antiviral, biconvex, underdeveloped, overeat, postposition, prehistoric, undersized, prorector, reshape, coexist, bifoliate, subnormal, interplanetary, intraocular.

Ex.2. Pick out the pairs of words, which have the same root, and translate them.

Invariable, slight, reconsider, selector, ethics, similitude, inconvenient, medication, disappear, purely, physical, finely, pressure, variety, medicinal, slightly, impure, appearance, similarly, convenience, physician, fineness.

Ex.3. Find the verbs among the following words:

Form, dry, available, state, technique, volume, shape, circular, common, define, use, important, require, weight, deep, influence, increase, essencially, amount, smooth, improve.

Ex.4. Ask questions. Start with the question-word given in brackets:

Example: Sticking of the tablets may occur when there is too much moisture in the drug material. (When?) – When may sticking of the tablets occur?

1. The correct pressure must be applied in order to avoid ejection problems. (Why?)

2. The preparation should contain not less than 99.5 per cent of acetyl – salicylic acid. (How much?)

3. Reduction may occur if organic compounds are present. (When?)

4. Seeds must be planted deep enough to have a sufficient supply of moisture. (Why?)

5. Gums may form in the plant as normal constituents. (Where?)

6. Short-sighted people have to wear spectacles. (What?)

7. Substances of such complexity can crystallize under ordinary conditions. (When?)

8. Digitalis should be kept in a container with a dry atmosphere maintained. (Where?)

9. After drying-out the substance they could determine its melting point. (What?)

10. Patients must use sedatives with care. (How?)

Ex.5. Put the verbs into Past Simple. Translate:

Example: He cannot translate this text without a dictionary.→ He could not translate this text without a dictionary.

1. Digitalis may easily be grown from seeds.

2. Can’t you dissolve this substance?

3. Something is wrong with the X-ray apparatus: we cannot start it.

4. Ergot alkaloids may be discussed later.

5. As soon as the freshers are allowed to use the university library, they can take every book they need.

6. Nobody is able to help him with this experiment.

7. He really must work hard as he wants to enter the University.

8. Can you tell me the way to the nearest chemist’s?

9. She has a flu, she must get intramuscular injections of antibiotics three times a day.

10. Overdosage of this medicine may cause unfavourable reactions.

Ex.6 Choose the correct verb form, Active or Passive. Translate:

1. If injected in concentrations over 200mg per cb. cm, the drug (may cause, may be caused) toxic effects.

2. It is expected that satisfactory results (could equally obtain, could equally be obtained) upon administration to humans.

3. It (could observe, could be observed) that the extent of absorption depended on the compound being absorbed.

4. At a chemist’s one (can buy, can be bought) various medicines for intramuscular and intravenous injections, for oral administration and for external use.

5. When my sister got ill, she (had to order, had to be ordered) lots of medicines at the chemist’s.

6. The filter (may make, may be made) of paper, paper pulp, sand etc.

7. The dentist (has to extract, has to be extracted) your bad tooth.

8. The method proposed (can determine, can be determined) ampicillin in pure form or in capsules.

9. Tablets which (have to coat, have to be coated) after compression must have a deep convex shape.

10. The scientist (should do, should be done) numerous experiments on animals before treating people with a new medicine.

Ex.7. Translate into English according to the model; use the words from the text:

Model: якомога скоріше – as quickly as possible

якомога тонший – аs thin as possible

Ex.8. Find the English equivalents in the text:

Виготовлення таблеток; у сухому стані; медичні таблетки; найбільш поширена форма; з плоскими або злегка випуклими бічними сторонами; у випадку; попередні міркування; конкретні форми і розміри; приємний зовнішній вигляд; подібним чином; призначений для; якомога скоріше; тієї ж самої ваги; повинні розчинятись повільно; для зручності користувача; тривалий ефект; дієвість таблетки; повинні вкриватись оболонкою; на додаток до вищесказаних міркувань; коефіцієнт стискання; порошок; з чисто фізичної точки зору; дрібно подрібнений стан; навіть без якихось допоміжних речовин; для внутрішнього вживання; у той же час; щоб покращити його ковзкі властивості.

Ex. 9. Are the sentences true or false? Correct the false sentences:

1. The most common form of medication for the administering of a medicine in a dry state is a powder.

2. There can be circular, rectangular, triangular, and other shapes of tablets.

3. A table must be as thick as possible if it is meant for making solutions.

4. A lasting effect can be provided by a thin and flat tablet slowly dissolving in the mouth.

5. Increased hardness and a deep convex shape are necessary for tablets, which are to be coated after compression.

6. The density and compression ratio of tablet material may influence the choice of tablet dimensions.

7. No auxiliary substances are needed to make tablets from substances like lactose.

8. Great pressure in tablet making may cause ejection problems.

Ex.10. Answer the questions on the text:

1. What is the tablet?

2. What is the most common shape of tablets?

3. What other shapes do we use?

4. Do you think it is important that a tablet would have a pleasing appearance?

5. What are the best sizes and shapes of tablets meant for making solutions?

6. What are the preferrable sizes and shapes of tablets which are to dissolve slowly in the mouth?

7. What tablets must have a deep convex shape and be harder than other tablets?

8. What other factors may influense the choice of a shape and size?

9. How can you define the technique of tabletting?

10. Why may the addition of auxiliary substances be necessary in tablet making?

11. Why are glidants added to the tablet material?

12. What are lubricants added for?

Unit 11: Grammar: Participle I, II.

Remember the following words:

1. tuberculosis [tju:,bə:kju’lousis] – туберкульоз

2. affect [ə’fekt] – 1) діяти, впливати

2) торкатися, зачіпати

3. lesion [‘li:Зən] – ушкодження, ураження (тканини, органу)

4. plummet [‘plΛmit] – важкість

5. plummeted [‘plΛmitid] – обтяжений

6. estimate [‘estimeit]– оцінювати

7. lurk [lə:k]– залишатися непоміченим, ховатися.

8. delay [di’lei] – відкладати; уповільнювати; затримка; уповільнення.

9. macrophage [‘mækriofeig] – бактеріофаг, бактеріальний вірус

10. emergence [i’mə:dЗəns] – поява

Tuberculosis – The Return of a Killer

Tuberculosis (TB) has been killing for a long time. It affected the Incas of Peru long before Europeans sailed to South America. It attacked Egyptians in the days when pharaohs ruled in splendour. Writings from of old show that TB stalked both great and small in ancient Babylon, Greece, and China.

From the 18th century until the early 20th century, TB was the leading cause of death in the Western World. Eventually, in 1882, German doctor Robert Koch officially announced his discovery of the bacillus responsible for the disease. Thirteen years later Wilhelm Roentgen discovered X-rays, making it possible to scan the lungs of living persons for signs of tubercular lesions. Next, in 1921, French scientists created a vaccine against TB.

Physicians sent TB patients to sanatoriums. These hospitals were frequently located in the mountains, where patients could rest and breathe fresh air.

Then, in 1944, doctors in the United States discovered streptomycin, the first antibiotic found to be effective against TB. The development of other anti-TB drugs quickly followed. At last, TB patients could be cured, even in their own homes.

As infection rates plummeted, the future looked rosy. Sanatoriums closed down, and funding for TB research dried up: Prevention programs were scuttled, and scientists and doctors looked for new medical challenges. In the mid - 1980's TB began to make a dreadful and deadly comeback. Up to two billion people - one third of the world's population — are already infected with the TB bacillus, a type of bacterium. In addition, another person is infected with TB every second!

In 1995 the number of people with full flown TB was about 22 million. Nearly three million died, most of them in the developing world.

The reason of comeback of TB is that during the past 20 years, TB -control programs have deteriorated or disappeared in many parts of the world. This has led to delays in diagnosing and treating those with the disease. That, in turn, has resulted in more deaths and the spread of the disease. Another reason for the re-emergence of TB is the growing number of poor, malnourished people who live in crowded cities.

In most people TB infection never progresses to the point of causing sickness because the TB bacilli are imprisoned within cells called macrophages. There, they are locked up by the person's immune system, particularly by the T lymphocytes or T cells. The TB bacilli are like cobras secured in baskets with tight - fitting lids. The baskets are the macrophages, and the lids are the T cells. When the AIDS virus arrives on the scene, it kicks the lids off the baskets. When that happens, the bacilli escape and are free to despoil any part of the body.

The final factor that is making the fight against TB more difficult is the emergence of drug-resistant stains of TB. These superstrains threaten to make the disease incurable again, as it was in the era before antibiotics.

Treating patients with multidrug resistant TB is not just difficult, it is also expensive. The cost can be nearly 100 times more than the cost of treating other TB patients. In the USA, the medical bill for the treatment of a single case might exceed $ 250 000. It is estimated that about 100 million people worldwide may be infected with drug-resistant strains of TB.

World List

1.writings from of old show — старовинні писання виявляють;

2.when pharaohs ruled in splendor — у дні розквіту правління фараонів;

3.to stalk both great and small — підстерігати як вельмож так і простолюдинів;

4.to scan the lungs of living persons for signs of tubercular lesions — розглядати легені живих людей для виявлення ознак туберкульозних ушкоджень;

5.as infection rates plummeted — оскільки рівень заражуваності знизився;

6.funding for TB research dried up — фінансування досліджень туберкульозу скорочено;

7.prevention programs were scuttled — впровадження програм по запобіганню хворобі — припинено;

8.to look for new medical challenges — братися до розв'язання нових медичних проблем;

9.to make a dreadful and deadly comeback — повернувся, щоб навівати жах і сіяти смерть;

10.TB-control programs have deteriorated or disappeared — було частково або повністю зупинено впровадження програм контролю над туберкульозом;

11.reason for the re-emergence of TB — причина повернення туберкульозу;

12.malnourished people — люди, що недоїдають;

13.baskets with tight-fitting lids — кошики з кришками, що щільно закриваються;

14.to kick the lids off the baskets — зривати з кошиків кришки;

15.is the emergence of drug-resistant strains of TB — з'явилися штами туберкульозу, які опірні багатьом лікам.

Date: 2015-10-18; view: 1056; Нарушение авторских прав