Chronobiology | How we do R&D | Explore GSK | GlaxoSmithKline


Does it make a difference what time you take your medicine? Find out about the research we are doing into chronobiology – the science of the night and day rhythms in the human body.

As the saying goes: timing is everything. And timing can potentially mean more than you realise when it comes to medicines.

For some medicines, the time of the day that you take it can make a difference to how well it works. For example some statins - which are used to reduce cholesterol - are recommended to be taken in the evening, as the body produces most cholesterol while we sleep.

Our researchers have joined forces with the University of Manchester to uncover more about how the time a medicine is taken may influence how effective it is.

They will be studying aspects of circadian rhythm - the name given to our internal ‘body clock’ that regulates the 24-hour biological cycle in animals and plants. This cycle is dependent on certain triggers, the main one being light.

An obvious example of circadian rhythm is that people generally feel awake and alert when it is light and then start to slow down or feel tired when it is dark. Jet lag happens when the circadian rhythm is disrupted, as your body keeps to its orginal cycle even though you may be in a new timezone.

Studies around circadian rhythms have discovered that many genes in our body are put into action only at certain times of the day or night. This means that timing the dose of a medicine to coincide with the time the gene will be read should provide greater effect.

Currently, many treatments are designed to be taken once in a 24-hour period. This makes it far more convenient for the patient and therefore more likely that they will take their medicine when they should. However, it could also mean the medicine may not be timed for optimal efficacy.

The ultimate aim when formulating a medicine is to come up with one that can be taken at a convenient time for the patient but which also 'kicks in' when it is likely to be most effective - whatever time of day that might be. 

Our investigations will try to see if the circadian rhythm of patients with inflammatory conditions such as rheumatoid arthritis or asthma differs from that seen in people without those conditions. 

The team will also try to understand how processes in the cells which are involved in the inflammatory process change over a 24 hour period, and whether these rhythms are altered by a chronic disease. The researchers are hoping this will set the scene for a study in people that could look at optimal circadian timing in medicine delivery.

Clock on side table next to woman sleeping

The term 'circadian' comes from the Latin circa, meaning 'around', and dies, meaning 'day', meaning literally, 'around the day'.