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How the delivery of medicines has improved

Just as the way we travel has developed over the years - from foot, to car to aeroplane - so has the way medicines are delivered to the body.

In the early development of medicines, the main methods of giving medicines was by pills (which were handmade by skilled apothecaries, or chemists), liquids and topical (rubbed onto the skin) applications such pastes and ointments. As technology progressed, newer approaches have made drug delivery to the various sites of action easier and more effective.

Pharmaceutical companies discovered that by changing the way they made tablets and capsules they could reduce side effects or make a medicine effective for longer in the body by creating a tablet or capsule that only released a small but controlled amount of medication at a time. These new forms include:

Enteric coated tablets

Tablets can be coated with special materials designed to begin releasing their ingredients once the medicine has passed through the stomach. This helps avoid stomach upset, and protects the drug from the acid in your stomach, which might render the drug useless. Coated tablets must be swallowed whole, as if you crush or chew these tablets the coating is destroyed and the benefit will be lost. 

Slow-release (or modified-release) tablets and capsules

These slowly release their ingredients over a longer period of time. These should also be swallowed whole, without being crushed or chewed because otherwise the technology that controls the slow-release mechanism can be destroyed.

There are occasional exceptions to this rule: some slow-release tablets can be halved, and some slow-release capsules can be emptied, provided the pellets inside the capsules are not chewed or crushed once emptied out. Check with your doctor or pharmacist first.

What if I have difficulty swallowing medicines?

If you are having difficulty swallowing your tablets or capsules, it is important that you follow the instructions for taking them. These instructions are usually printed on your label and can also be found in the information leaflet supplied with your medicine. If you are still having difficulty taking your medicines, then your doctor or pharmacist can help with other options, such as using liquid preparations. (Also see our topic Pharmacy labels - what do they mean?) 

Other forms of medicines

Tablets and capsules are not the only way of getting medicines into your body. Some medicines are available in suppository form for insertion into the rectum, which is good for people who cannot swallow medicines or when they are vomiting. There are also vaginal preparations. Drugs can be inhaled into the lungs, placed on the skin as ointments, creams or patches or injected into a vein under the skin.

Patches

Most people will think of smoking cessation when they think of patches (nicotine patches), but more medicines are now becoming available in this form, such as hormone replacement therapy, and pain relief patches.

When using patches, it is very important not to cut the patch in half.as this may cause a breakdown in the release mechanism of the patch, which could cause a larger than usual amount of drug to enter your system. Wash hands after applying the patch to get rid of any drug that might be there.

Inhaler devices   

There are two main types of inhaled devices: those that deliver medicines to the nasal passages (nasal sprays) and those that deliver medicine to the lungs (inhalers).

Nasal sprays often use a pump action to deliver the medicine. These devices sometimes need priming before first use: pump them two or three times until you see the mist coming from the nozzle. Do not tamper with the device by sticking a pin into the nozzle as this can stop it working altogether. If you can't see a spray after several pumps, take it back to your pharmacy, and ask them to check it for you.

Lung inhalers come in a variety of forms, which may suit different people. Some types of inhaler need a certain amount of co-ordination to ensure maximum delivery. Some contain very small amounts of powder, and it may be difficult to tell if you have used the inhaler correctly. Others need to be loaded from a capsule every dose or every few doses. It is important that you know how to use your inhaler correctly. Your doctor or pharmacist can check your inhaler technique or demonstrate how to use new inhalers.

Original material provided by Pauline Hamilton, Dip. Pharm, MRPSGB. Reviewed by everybody, March 2006.