Different types of tablets
Increasingly tablets are being made which are suitable for patients who cannot swallow normal tablets. These are listed below with examples provided.
Dispersible or effervescent tablets
These tablets are designed to be added to water just prior to swallowing. They are frequently quite large and can contain large amounts of sodium. The size prevents patients from taking many of them, which is helpful for soluble paracetamolproducts for instance however the sodium content can cause problems in patients where sodium intake is restricted.
These tablets are designed to be dissolved under the tongue, are rapidly absorbed through the tongue and therefore work quickly. This is why some tablets for the treatment of angina pain and others for general pain are formulated in this manner. The disadvantages are that they require sufficient saliva production and due to quick absorption are more likely to cause side effects and are more quickly removed from the body.
Buccal tablets are intended to be placed on the gum or in the cheek to allow the drug absorbed. Because the medicine can be held for a longer period of time on the gum, medicines which need to be released at a slower rate than sub-lingual tablets can be given via this route. This route is used for anti-nausea drugs and nicotine replacement gums. Anti-nausea medicines are particularly suitable for buccal administration as the nausea itself can cause swallowed tablets to be vomited and therefore rendered ineffective.
Melt tablets are placed on the tongue and are designed to dissolve directly in the mouth’s saliva. The contents are then swallowed with saliva and consequently water does not have to be administered with these medicines. This is particularly useful in patients who are at risk of aspiration and therefore unable to swallow tablets with water concurrently.
Oro-dispersible tablets are similar to melts and are designed to disperse in the mouth and to be washed down with saliva. As with sub-lingual, buccal and melts, oro-dispersible products require an adequate amount of saliva production. Some oro-dispersible tablets consist of coated granules and therefore it is not appropriate to crush the oro-dispersible product prior to dispersion.