Pharmacotherapeutics in space & pharmacology in space is an integral part of various space exploration programs that study the effects of drugs in space. The goal of various is to provide diagnostics, pharmaceutical preparations & therapeutics to maintain the good metabolism of living being in space. Get an overview of what is pharmacotherapeutics in space.
What is pharmacotherapeutics in space & aerospace pharmacy exactly mean?
The concept of aerospace pharmacy, pharmacotherapeutics or pharmacology in space might sound new but it isn’t, as it dates way back in the century. The concept grew in-parallel to aeronautics and the need is ever demanding. It is a field in pharmacy that is simply calling for attention of pharmacology & pharmaceutical practitioners to implement their knowledge for understanding of the metabolism of a living being towards drugs in space. It also highlights the difficulties in translating earth-based drug studies to a meaningful interpretation of drug stability and effectiveness in space.
Pharmacotherapeutics in space
Pharmacotherapeutics in space is the study of the therapeutic uses and effects of drugs in space. The factors that it takes into consideration are;
1.Stability of pharmaceutical dosage forms
2.Medical practices based on evidence
3.Study of pharmacokinetic(pk) and pharmacodynamic(PD)
4.Systemic evaluation of therapeutic monitoring
5.Facilitate technologies for drug treatment
Monitoring and management of space missions under keen observation and record results accordingly.
Pharmacology in space
Pharmacology in space is the study of the use of pharmaceutical drugs during spaceflights. The studying of drugs in such condition is necessary because the effects of drugs lose their efficiency during the flight and hence the research is an important part of such inflight missions.
The research around this field is still primitive and is based on experiential learning. After studying and working around it all the shortcomings in the previous mission can be overcome. Therefore, later put to use in the forthcoming missions. At present, the knowledge of the effects of spaceflight on medication stability continues to be under research and requires a long way to go. Lack of requisites to track the medication use and their response has impeded the collection of effective data. Hence the pharmaceutical effectiveness is difficult to characterize.
Difficulties in space from a pharmaceutical viewpoint
The environment in space is entirely different from the earth. The researchers have to keep in mind that degradation of medication is faster in space than on the ground. Pharmacokinetics and pharmacodynamics of the body changes in space. Microgravity or zero gravity comes into play and this is a major property of the space that changes everything around pharmacotherapeutics in space. The ultimate ambition of researchers is the adoption of the microgravity environment in space and then the earth’s environment after astronauts return.
Understanding Mircogravity with respect to pharmacotherapeutics in space
Study of microgravity; weightlessness or free fall, in other words, zero gravity is deeply associated in understanding of what is pharmacotherapeutics in space. Microgravity is much lower gravity than on earth. The acceleration due to gravity or simply gravity on earth is 9.807m/s2. Gravitational force is a natural phenomenon which brings objects possessing mass together. Due to gravity on earth, we have a weight which is the force we exert on earth. But in space due to zero gravity astronauts fly all around and experience weightlessness.
Effects of microgravity:
Extreme variation in temperature, pressure and radiation levels causes utmost health fatalities.
In lower gravities, the heart does not need to do as much hard work as it does on earth to pump blood to the upper parts of the body. This results in an increase in the volume of blood in the upper body. Microgravity causes loss of proprioception changes in fluid distribution Absence of gravity leads to expansion of vertebrae which increases the height of an astronaut by 2 inches.
Consequences of microgravity on human body:
Pharmacology in space is the study of drugs in space which comprises of two main divisions; Pharmacokinetics and Pharmacodynamics.
Pharmacokinetics (PK) defined as the metabolism of a drug through the body and Pharmacodynamics (PD) is the body’s biological response to drugs. Study of both is important as to provide a better understanding of pharmaceutics in space. Changes in both PK and PD properties due to fluid shift in microgravity are the base for research around the field.
The effects of microgravity on a human body:
- Exposure to microgravity has an altered result on the functioning of the cardiovascular, neurosensory and Musco-skeletal system.
- Decrease in the cardiovascular system, decreased production of red blood cells, cardiac arrhythmia, fluid redistribution.
- Balance disorder, loss of eyesight, disruption of taste, decreased mental health, orthostatic intolerance.
- Bone loss, enlargement of bones, muscle loss, spaceflight osteopenia, decompression sickness.
- Exposure to continued radiation, injure the body which has later implications on the body.
- An astronaut experiences loss of consciousness as soon as they reach the earth’s atmosphere.
- The fluid shift causes body mass loss.
- Barotraumas, sleep disorder, excess flatulence and immune suppression are the most common disorder recorded in astronauts.
- Hampering of Metabolism: Impairment of protein metabolism, lowering of plasma protein, impairment of renal functioning.
As soon as the astronauts reach back to earth their health falls back and reports of delayed responses are generated. Due to the weakened immune system, the chances of fatalities increase and may cause greater risks to human health.
Pharmaceutical preparation for astronauts before the mission :
For an astronaut to sign-up for a mission, there are several physical tests he has to go through as per the study of pharmacotherapeutics in space. Disease symptoms, illness or medications are discussed before the mission with a flight surgeon without any requirement for documentation. Whereas OTC (Over the counter) drugs are taken with proper consultation with proper documents which is needed to be submitted prior mission. According to a recent study, 453 medication uses were reported per crew member during a particular mission.
Stability of drugs in space:
1.The low efficiency of a drug in outer-space called for attention very late in space pharmaceutical research field. Due to which reports of the efficacy of medications are lacking for future references. When a drug maintains its physical and chemical properties over time, it finds its role as a stable drug.
2.Any alteration in its dissolution and solubility of the medication, alteration of excipients, excipient active ingredient interaction or toxic degradation and loss of potency marks the lowering of drug stability.
3.Another fact that we should keep in mind is that, if the concentration of the API (Active Pharmaceutical Ingredient) in the drug fails to meet United States Pharmacopoeia requirements then instability or degradation of a drug comes into consideration. Any alteration would affect drug potency and efficacy.
A federal program developed by the U.S Department of Defence in association with FDA called SLEP (Shelf Life Extension Program) to put off the cost of the medication & drugs in space. To determine if the use of a drug can be beyond its expiration date, it is necessary that only those medicines make it to the medication kit in the mission that has at least 2 years of expiration date. A few drugs listed under stable category in the SLEP studies are Ciprofloxacin, Phenytoin, Promethazine and Acetaminophen.
Inefficiency Of Drugs in Space:
In the year 1999, Putcha et al presented a study among the 13 medications which he characterized as “mildly effective” or “ineffective” in treating the symptoms up in space. Another similar study published later in 2014 by Banger et al, confirmed the ineffectiveness of drugs in space. He reported an anecdotal study about how the astronauts had to take two sleep medications due to the ineffective response of the first.
However, the conclusion made by both the studies cannot be considered because it lacks proper documentation, anecdotes and voluntary reporting. This makes the report uncertain and the result unreliable. Another doubt that arose simultaneously was that the metabolism of the body can be altered by the change in the environment. So, the consideration of the environment should be taken while diagnosing the results.
If the study of drugs suits to your interest you’ll love reading one of our article here
What are the bodily changes during a space-flight & how it helps the study of drugs in space or pharmacotherapeutics in space?
A lot of changes in the metabolism of a human body take place during a space mission. The various reasons described in the context above contribute to researches taking place all around the globe. Data accumulated over the years out of various space exploration program do contribute in testing the efficiency of drugs in space, their stability & analyzing medication schedule. This data collected will lead to an overall progress in the research approach of people studying pharmacology & pharmacotherapeutics in space
Some of the bodily changes are as outlined below:
Gravitational unloading causes fluid shift which then leads to alteration in hepatic blood flow mechanism and variable enzyme activity. Microgravity is responsible for delayed gastric emptying. Varied protein expression, altered serum albumin levels and altered renal blood flow may further affect drug absorption, distribution, metabolism and excretion. The unequal distribution of the drugs that the astronauts take affects its efficiency. The alteration of gastrointestinal absorption takes place due to poor pharmacokinetic behaviour of a drug. Therefore, leading to it’s reduced stability.
Sample Testing for pharmacokinetic behavioral changes:
For testing the PK/PD studies, researchers collect saliva samples instead of blood samples. This is due to the ease of collection and storage. According to studies, the method is highly flawed because of its unpredictable nature. Furthermore, its concentration does not correlate to plasma concentration. The comparison of gastrointestinal transit time is only possible after taking pre-flight and in-flight salivary levels. Bioavailability is another parameter to test the efficiency of a drug.
Permittance of drugs in space
Experiences from previous Apollo missions made the replacement of Marezine with a combination of Scopolamine and Dextroamphetamine for space motion sickness after efficiency studies. Some of the recent studies & observations show below drugs that are permissible. (check this statement)
- Aspirin for headache and pain
- Secobarbital for sleeping disturbances
- Diphenoxylate (lomotil®) as an anti-diarrheic
- Actifed which is a combination of antihistaminic, anti-inflammatory, analgesic and antipyretic
- After a sudden unfortunate incidence of cardiac arrhythmia was reported in Apollo-15 mission, potassium salt made its place in the space mission medical kits.
- Apollo -13 mission witnessed a sudden UTI in-flight which was later treated by Colistin (Colimycin®).
- Vitamins, ophthalmic antibiotic ointments and decongestants were added very late to the emergency kits.
Conclusion of the above context that highlights pharmacotherapeutics in space :
The research in PK/PD studies, formulation studies, drug dosage form studies, physiology studies, bioavailability studies and exploration towards the advancement of pharmacotherapeutics in space will eventually lead to the development of a novel drug delivery system for chronic and acute symptoms of diseases in space, attenuates pharmacotherapeutic risks by identifying and giving safe and effective tools for diagnosis, pharmaceutical preparation, intervention strategies and therapeutic procedures to check chemical and pharmaceutical studies in space.
There are numerous opportunities in regards to the study of of pharmacotherapeutics in space laid down by various space researches & pharmaceutical organizations where anyone intreseted can contribute. Just for reference you can go through the official site (https://www.nasa.gov/content/pharmacotherapeutics/ ) for deeper insights on above subject.