No one thinks shots are fun. But the diseases they prevent can be very serious and cause symptoms that last much longer than the temporary discomfort of the shot.
To make life easier, now you can get immunizations at many pharmacies. Although some medicines require a prescription , some are available in stores.
You can buy many medicines for pain, fever, cough, or allergies without a prescription. But just because a medicine is available over-the-counter OTC , that doesn't mean it's free of side effects. Take OTC medicines with the same caution as those prescribed by a doctor.
No matter what type of medicine your doctor prescribes, it's always important to be safe and follow some basic rules:. Taking medicines may feel like a hassle sometimes. But medicines are the most effective treatments available for many illnesses. If you ever have any questions about what a medicine does or how you should take it, talk with your doctor or a pharmacist. Understanding Medicines and What They Do.
Larger text size Large text size Regular text size. What Are Medicines? But medicines can be delivered in many ways, such as: liquids that are swallowed drops that are put into ears or eyes creams, gels, or ointments that are rubbed onto the skin inhalers like nasal sprays or asthma inhalers patches that are stuck to skin called transdermal patches tablets that are placed under the tongue called sublingual medicines; the medicine is absorbed into blood vessels and enters the bloodstream injections shots or intravenous inserted into a vein medicines No medicine can be sold unless it has first been approved by the U.
Double-check that you have the right medicine. If you get the same prescription filled more than once, check that it's the same shape, size, and color as the last time. If not, be sure to ask the pharmacist about it. Read the label and follow directions. Ask if you have questions.
Take medicines exactly as prescribed. If the instructions say take one tablet four times a day, don't take two tablets twice a day. It's not the same. Ask if the medicine is likely to affect everyday tasks such as driving or concentrating in school. Don't take more medicine than is recommended. Very few molecules make it this far; those that do can perhaps be turned into a safe and usable drug.
The process is still far from over. Until now the drug has been limited to the lab, but clinical trials will test the drug on humans. This highly sensitive stage of the process is carried out in four phases and follows strict scientific and ethical guidelines, most notably that participants give their informed consent: they understand how the drug works, what the trial is testing, and all the risks involved.
Already, exhaustive efforts have been made to confirm that the drug is safe and effective on humans, but even at this advanced stage of development the probability of success remains low: Only around 10 percent of drugs that go to clinical trials ever make it onto pharmacy shelves.
In Phase II the drug is given to small numbers of patients suffering from the target illness to find the right dosage, frequency, impacts of administering with food and delivery method for the drug.
If the results are consistently good, Phase III trials seek to prove the drug across statistically significant numbers of patients—perhaps thousands all around the world. Throughout the clinical trials, results are diligently monitored, analyzed, and published for peer review until the drug is established as safe and effective. The challenge facing medicinal science is to fill the demand for new drugs. Drug discovery relies on the collaborative efforts of researchers including chemists, biologists, and physicians.
Chemists build molecules that may eventually become drugs while biologists investigate the relevant molecules that cause diseases. Together, scientists select drug targets in the form of large biomolecules such as proteins or cancer cells, then search for molecules that will disrupt the protein or kill the malignant cell.
Chemistry plays a vital role through its ability to decipher molecular interactions that define the way drugs cure diseases. Scientists try to find out as much as possible about the structures of the key and lock as well as how different keys interact with the lock.
The challenge lies in finding a way to test the plethora of available keys against the vast number of accessible locks. To complicate matters more, a lock may not be found for every disease and one key may fit into multiple locks.
Historically, medicines were administered in the form of herbal concoctions, and many traditional medicines continue to be taken this way. As science advanced, chemists were able to extract the active ingredients from natural sources to make more potent medicines. For example, aspirin acetylsalicylic acid was discovered from the willow tree, the bark of which was used in traditional herbal remedies [].
When a natural source is not readily available, chemistry often steps in to provide practical alternatives. In the early s, the Pacific yew tree Taxus brevifolia was found to produce the blockbuster anticancer drug paclitaxel Taxol []. Initially, Pacific yew populations declined because the harvesting process stripped the bark and killed the trees. Public outcry against this method led to an improved process that generated paclitaxel by isolating part of the molecule from European yew needles, which was then chemically modified to produce the complete drug.
Currently, paclitaxel is produced by isolating plant cells from twigs and needles and growing the cells in a process called plant cell fermentation; this process is more sustainable because it spares trees and reduces chemical waste []. Clinical trials may also continue.
Regulatory authorities may insist on phase 4 trials for post-marketing safety surveillance pharmacovigilance or they may be undertaken by the company to enable them to target distinct markets. For example, to enable the drug to be used in patients with complex medical problems or pregnant women who are unlikely to have been involved in earlier trials, and to ensure that they do not interact with other drugs.
Pharmaceutical companies will patent any molecule that shows promise early in the development process. Patenting prevents other companies copying it for 20 years and covers many aspects of the intellectual property of a drug, including its manufacture, formulation and, in some cases, its use. The purpose of a patent is to enable the pharmaceutical company that developed it to recoup their development costs and to make a profit to cover the development costs of drugs that failed during the testing process, as well as to invest in the development of future innovative drugs.
By the time a drug has undergone the required testing and been licensed, half the patent period will usually have expired. Once a patent on a drug has expired generic versions of the drug can be manufactured and marketed. For some drugs the period of patent protection can be extended for up to a further five-and-a-half years, so long as this does not take the time in which the drug is under patent protection beyond 15 years after the date it received regulatory approval.
As drugs and their development have become more complex and expensive, so have the demands for information from the regulatory agencies. In response, communication channels have opened up between drug companies and regulators well ahead of submissions to help ensure that companies are compiling all the relevant data required for a successful submission. The MHRA has set up a dedicated innovation office to provide advice and support to companies.
Its main focus is to aid new drug developers and companies developing unique products such as gene and cell therapy, nanomedicines, or treatments involving new delivery systems or produced through novel manufacturing processes.
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