What factors does a doctor consider when writing a prescription?
The 6 main variables of medication prescribing
- Height and weight.
- Sex.
- Age.
- Existing medical conditions.
- Drug interactions.
- Medication intolerance.
What are the factors that help a doctor in his choice and use of drugs?
In the studies, it was determined that 24 different factors affect the physicians’ choice of drugs, and the most frequently cited factors were found to be the originality of the drug, the price of the drug, the level of education of the physicians, the drug efficacy and the socioeconomic status of the patients.
What are the factors which may influence over medication?
The primary factors that influence drug effect are the type of drug and the quantity used….The effect of any drug on an individual is the result of three interacting factors:
- the drug itself.
- the individual user.
- the environment in which drug use occurs.
What are 4 factors that affect absorption of a drug?
Several factors can affect the absorption of a drug into the body. These include: physicochemical properties (e.g. solubility) drug formulation (e.g. tablets, capsules, solutions)…the physicochemical properties of the drug, such as its:
- lipid solubility.
- molecular size.
- degree of ionization.
What factors can affect drug metabolism in an elderly?
Aging results in a number of significant changes in the human liver including reductions in liver blood flow, size, drug-metabolizing enzyme content, and pseudocapillarization. Drug metabolism is also influenced by comorbid disease, frailty, concomitant medicines, and (epi)genetics.
What is the most common medication problem in the elderly?
Warfarin is one of the most common causes of medication-related hospitalizations in older adults. To reduce the risk of serious problems, one may need to apply extra care in monitoring warfarin effect (via the prothrombin blood test) and extra care in checking for interactions when a new drug is prescribed.
Why are elderly more sensitive to drugs?
Increased Sensitivity to Many Drugs: The problems of decreased body size, altered body composition (more fat, less water), and decreased liver and kidney function cause many drugs to accumulate in older people’s bodies at dangerously higher levels and for longer times than in younger people.
What is the most common adverse drug effect seen in the elderly?
Adverse drug events occur in 15 percent or more of older patients presenting to offices, hospitals, and extended care facilities. These events are potentially preventable up to 50 percent of the time. Common serious manifestations include falls, orthostatic hypotension, heart failure, and delirium.
What are examples of adverse effects?
Examples of such adverse drug reactions include rashes, jaundice, anemia, a decrease in the white blood cell count, kidney damage, and nerve injury that may impair vision or hearing. These reactions tend to be more serious but typically occur in a very small number of people.
What are four reasons why adverse drug effects are increased in the elderly?
ADR risk increases with age-related changes in pharmacokinetics and pharmacodynamics, increasing burden of comorbidity, polypharmacy, inappropriate prescribing and suboptimal monitoring of drugs. ADRs are a preventable cause of harm to patients and an unnecessary waste of healthcare resources.
What happens when drugs cross the blood brain barrier?
The blood–brain barrier (BBB) prevents entry into the brain of most drugs from the blood. The presence of the BBB makes difficult the development of new treatments of brain diseases, or new radiopharmaceuticals for neuroimaging of brain.
Which drug Cannot pass the blood brain barrier?
(A) Passive diffusion: fat-soluble substances dissolve in the cell membrane and cross the barrier (e.g., alcohol, nicotine and caffeine). Water-soluble substances such as penicillin have difficulty in getting through.
What Cannot cross the blood brain barrier?
Such substances include lipid-soluble substances (e.g., oxygen, carbon dioxide). Hydrophilic substances, for example, hydron and bicarbonate, are not permitted to pass through cells and across the blood-brain barrier.
Why would a drug most likely be able to cross the blood brain barrier?
Most drugs cross the BBB by transmembrane diffusion [9]. This is a non-saturable mechanism that depends on the drug melding into the cell membrane. A low molecular weight and high degree of lipid solubility favor crossing by this mechanism.
How do substances cross the blood brain barrier?
Substances cross the blood-brain barrier (BBB) by a variety of mechanisms. These include transmembrane diffusion, saturable transporters, adsorptive endocytosis, and the extracellular pathways.
Can caffeine cross the blood brain barrier?
Caffeine is both water and fat-soluble, meaning it can actually get through the blood-brain barrier and stimulate the brain directly. But it also shares similarities to adenosine, a body nucleoside that scientists believe tells the body it’s tired.
How drugs are delivered to the brain?
The various strategies that have been explored to increase drug delivery into the brain include (i) chemical delivery systems, such as lipid-mediated transport, the prodrug approach and the lock-in system; (ii) biological delivery systems, in which pharmaceuticals are re-engineered to cross the BBB via specific …
Which organs are affected by ADR?
Idiosyncratic adverse drug reactions can affect a number of different organs, including the liver, skin, kidney, heart and muscle, and, with some drugs, more generalized hypersensitivity reactions can occur.
Which drugs can easily pass the placental barrier?
Zofran (ondansetron) has properties that cause it to easily cross the placenta in substantial amounts. Just for example, it has great lipid solubility, low molecular weight (365.9 daltons), and a measured in vitro plasma protein binding of 70% to 76%.