Chronotherapy involves altering the timing when taking medications. This helps to improve the overall control of a disease and to minimize side effects of the medication. Chronotherapy also refers to the manipulation of circadian rhythms to affect a disease state, and that is frequently employed in the treatment of sleep disturbances.
Several experiments done by scientists on animals and in humans have clearly demonstrated that all organisms are highly organized according to circadian rhythms. The studies have been conducted on over 100 different compounds. The results obtained have led several scientific societies to provide guidelines concerning the timing of drug dosing for anticancer, cardiovascular, respiratory, anti-ulcer, anti-inflammatory, immunosuppressive and antiepileptic drugs.
Absorption may be influenced by circadian rhythms and most lipophilic drugs seem to be absorbed faster when the drug is taken in the morning compared with the evening; for water soluble compounds, no circadian variation in the absorption of drugs has been found.
Drugs can be classified as hydrophilic or lipophilic depending on their ability to dissolve in water or in lipid-containing media. The predominantly lipophilic statins (simvastatin, fluvastatin, pitavastatin, lovastatin) can easily enter cells, whereas hydrophilic (liver) statins (rosuvastatin and pravastatin) are subjected to hepato-selectivity.
How drugs clear out of our systems are either on a high extraction ratio, low extraction ration, intermediate extraction ratio. As you can guess a high extraction ratio are drugs that rapidly and extensively cleared from the blood by the liver, (in a single pass). Clearance depends primarily on hepatic (liver) blood flow.
Low extraction ratio are not efficiently cleared by the liver and are extracted less quickly and incompletely from hepatic blood. Their clearance is relatively independent of hepatic blood flow. It is also primarily determined by the intrinsic metabolizing capacity of the liver and by the free drug fraction rate.
Intermediate extraction ration involves the hepatic clearance of these drugs is dependent on both hepatic blood flow, intrinsic metabolizing capacity of the liver and the free drug fraction. If you would like to learn about the ratio calculation please see the article “Hepatic Drug Clearance” on https://tmedweb.tulane.edu/pharmwiki/edu.
HOW IS YOUR CHRONO TYPE DETERMINED
In order for chronotherapy to work, the objective is to determine what the body’s circadian rhythms are. This can be determined in two different ways. One method is to alter the sleep-wake rhythms of patients to improve the sequels of several pathologies. Secondly, is to take into account the circadian rhythms of patients to improve therapeutics. Even minor dysfunction of the biological clock can greatly affect sleep/wake physiology causing excessive diurnal somnolence (also known excessive daytime sleepiness. A chronic condition that makes it difficult to stay alert and awake during the day), increase in sleep onset latency, phase delays of advances in sleep onset, frequent night awakenings, reduced sleep efficiency, delayed and shortened rapid eye movement sleep, or increased periodic leg movements (restless leg syndrome). Chronotherapy aims to restore the proper circadian pattern of the sleep-wake cycle, through adequate sleep hygiene, timed light exposure, and the use of chronobiotic medications, such as melatonin, that affect the output phase of circadian rhythms, open-heart surgery or the efficacy and tolerance to chemotherapy vary according to the time of day.
Chronotherapy is a behavioral technique in which bedtime is systemically delayed, which follows the natural tendency of human biology. Bedtime is delayed by 3-hour increments each day, establishing a 27-hour day. The procedure is maintained until the desired bedtime is reached (say 10 p.m.), when the normal 24-hour day is then established. This approach is favored by adolescents who are extreme night owls.
People who are night owls (like myself) tend to be most productive in the later evening. And people who are morning people tend to be most productive in the morning. People in their 50’s, 60’s. and 70’s may start to want to go to bed earlier and wake up earlier.
Factor like light, temperature and when you eat affect your circadian rhythm as well. These are known as zeitebers, external cues that impact your internal clock.
RESETTING YOUR RHYHMS
“Don’t expect to fix or reset your circadian rhythm overnight,” Dr, Roth, behavioral sleep medicine psychologist said. “It is for everything that goes on in our body. We have internal clocks for our hormones, your immune system, our digestion. Our organs all run on some sort of timing system.”
It can be hard to change sleep/wake habits. But over a weekend is a good time to practice. For example, if you currently going to sleep at 1 a.m., focus on going to bed at 12:30 a.m. and waking up at 8:30 a.m. for a week, and then shift those times back another half-hour the following week.
