Remember that it acts within about half an hour, is at its best one to two hours later and has normally worn off by four hours. If pain is persistent throughout the day, tablets need to be taken regularly. Of almost 20 compounds prescribable only one is available for purchase over the counter at high street chemists. It's duration of action is like Paracetamol so the tablets should be taken regularly for persistent pain or as required for intermittent pain, bearing in mind that tablets will be at their most effective about one hour after taking them. If this fails to help ibuprofen could be taken with Paracetamol.
Topical applications are also available.
The marketing suggestions that these remain localised under the site of application is not entirely true. Pharmacokinetic studies show that drugs are absorbed through the skin a little more slowly than via the gastrointestinal tract but that they then circulate around the body before reaching the target tissue. Tablet formulations are invariably less expensive. Replacement joints for the hip and knee have been available for some time and are very satisfactory. Replacement joints for the shoulder, elbow and ankle are not quite so well established but sometimes even one of these may be required.