In obese individuals, blood flow to fat is even poorer. Obese individuals are also likely to have a degree of heart failure which further decreases blood flow. This makes their fat a large compartment of potential distribution for lipophilic drugs which fills gradually, and then becomes a slowly emptying reservoir.
How does weight affect drug effectiveness?
Changes in body weight can influence the amount of medicine you need to take and how long it stays in your body. The circulatory system may slow down, which can affect how fast drugs get to the liver and kidneys.
What factors influence drug distribution?
The drug distribution is usually varied, and depends on several factors such as:
- Blood perfusion.
- Tissue binding (since drug binding is linked to the lipid content)
- Regional pH.
- Cell membrane permeability.
Does body size affect drug metabolism?
Physiological alterations to the body, such as increased adipose (fat) tissue, can affect distribution, metabolism and clearance of drugs from the body.
How does drug therapy affect obesity?
The goal of any treatment (including drug therapy) for overweight individuals is long-term weight reduction and improvement in overall health . Reduce and maintain weight loss – In short-term (6 to 12 months) clinical trials evaluating drug therapy, weight loss of 4 to 8 percent is typical .
How does genetics affect drug response?
Because of their genetic makeup, some people process (metabolize) drugs slowly. As a result, a drug may accumulate in the body, causing toxicity. Other people metabolize drugs so quickly that after they take a usual dose, drug levels in the blood never become high enough for the drug to be effective.
Does Weight Affect ibuprofen?
Ibuprofen volume of distribution was increased in obese subjects, and this increased distribution correlated positively with body weight (r = 0.82; P less than 0.001).
How does pH affect drug distribution?
So, in this case pH = pKa. Hence, when pH is equal to pKa, the drug is ionized halfly. Ionization of drug effects not only the rate at which the drug permeate membrane but also steady state distribution of drug between the body compartments, if pH difference is present between them.
How are drugs distributed?
After a drug is absorbed into the bloodstream (see Drug Absorption), it rapidly circulates through the body. The average circulation time of blood is 1 minute. As the blood recirculates, the drug moves from the bloodstream into the body’s tissues. Once absorbed, most drugs do not spread evenly throughout the body.
How does total body water affect drug distribution?
Total body water increases 6–8 liters during pregnancy and peaks at term . Increases in the volume of distribution for a medication will not alter the average steady state concentration, but will result in lower peak and higher trough concentrations.
What happens when an obese person is given with a lipophilic drug?
With lipophilic drugs (e.g., barbiturates, benzodiazepines), this parameter is significantly increased, explaining the prolongation of the plasma elimination half-life. For drugs that are almost equally soluble in water and oil (methyl xanthines, aminoglycosides), the V is slightly increased in the obese.
Does medicine go by weight or age?
Measure liquid medication by weight, not age
However, doctors say you should actually use your child’s weight to determine the right dose. “We calculate all medicine for children based on their weight,” Dr. Platt says. “So if you have a very small 8-year-old child, you might want to give them a dose for a 4-year-old.”
How does age affect drug action?
In general, as we age, total body water and muscle mass decrease while percentage of body fat increases. These changes can lead to drugs having a longer duration of action and increased effect. Drugs that were effective may become compounded and overexceed their therapeutic threshhold causing increased side effects.
What is the primary action of Orlistat a weight loss drug?
 The primary action of orlistat is local lipase inhibition within the gut. Systemic absorption is not necessary for the activity of orlistat. At its recommended dosage, it inhibits dietary fat absorption by approximately 30%.
Can I ask my doctor for weight loss pills?
Your doctor may consider a weight-loss drug for you if you haven’t been able to lose weight through diet and exercise and you meet one of the following: Your body mass index (BMI) is greater than 30.
What Contrave does to the body?
CONTRAVE® is a prescription-only, FDA-approved weight-loss pill believed to work on two areas of your brain—the hunger center and the reward system—to reduce hunger and help control cravings.