Breaking a Medicine Tablet: Is It Advisable?
The strength of a medicine depends on the patient’s age, body mass and the severity of the disease. Physicians have two major reasons on why they resort into advising a patient into breaking a tablet.
The first one involves economic reason. Hypertensive patients for instance, need their maintenance drugs daily to control high blood pressure. As a financial aid for these people, doctors tend to advise them to buy an antihypertensive drug with a double strength then have them divide the tablet into two or according to the required drug concentration. The first part is to be taken immediately while the other half or halves are saved for future uses. Medications with greater doses are often cheaper when divided or split.
The second reason is the drug unavailability. For a child patient, physicians instruct their secretaries to divide a tablet in cases that only an adult drug is available. A paracetamol 500mg tablet for example is cut so that half of it can be agreeable for a seven year old patient who only needs a 250mg strength.
Splitting a tablet is as simple as doing arithmetic, as logical as taking two 250mg capsules of amoxicillin if someone needed an adult dose or giving a baby a 3.5ml dose of a cough formula when no drops dosage form is available. But we may wonder, in the case of a tablet medication - are there no complications in cutting a tablet? Is this really recommendable for financial reasons?
Tablet types issues
We may notice several forms of tablets. Among these are the sublingual, the coated, the multi-layered etc. With the various types are different functions. Sublingual forms are to be taken beneath the tongue for emergency instances. While the effect is faster this way, sublingual types contains drugs that should only be absorbed through the oral mucosa because they are usually inactivated or not absorbed in the GIT.
With the erythromycin stearate as a film coated tablet, its form has two purposes; the coating prevents the patient from having stomach irritation because of the drug itself and the coating protects the inert substance from being destroyed by the gastric juices.
Tablet breaking is not advisable for tablet types cited above for this may decrease their effect and more to it, could harm the patient.
Not enough active constituents?
Besides the active ingredients responsible for the positive effect of the medication, a tablet may also include diluents, binders, lubricants, disintegrants and other additives to complete its form.
While diluents (E.g. Lactose) make up the major portion of the tablet, disintegrants are responsible for its breaking up in the process. Binders on the other hand, are adhesive substances that glue powder together that forms granules.
The manufacturing of a tablet involves mixing before compression. And one of the problems here is content uniformity. Content uniformity is defined as the equal distribution of the drug content in each tablet. This is determined on ten tablets. USP limit is 85-115% and is met if not more than one tablet is outside the limits.
One passing medicine tablet may have the appropriate active constituent but if we will cut it into two, there is no guarantee that a patient can also get half of the strength of the inert substance. It is also possible that the half side of the tablet contains the active constituent while the other half, the additives.
Will you consider breaking a tablet?
There are some tablets that are not designed to be divided. We can never be sure if we are going to get the exact strength of the drug when we cut it. Most people may claim that this method works and interestingly it does. We could think of it as a placebo effect but the thing is drugs even not divided equally have active constituents that can cure or harm. And we must be reminded that every individual has different body chemistry. Some may react to untoward reactions while the others may tolerate it. But just to be safe, tablets not designed to be cut should not be divided. There are the scored tablets or tablets that have lines - these are the tablet forms designed to be cut.
© Phoenix Montoya @ February 12, 2011
Compiled Notes in Manufacturing Pharmacy by Emma and Imelda G. Pena
Wilson and Gisvold’s Textbook of Organic Medicinal and Pharmaceutical Chemistry 4th edition
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