What are the three types of tolerance to a drug?
What are the three types of tolerance to a drug?
Molecular Mechanisms of Tolerance Historically, tolerance has been divided into three functional classes: acute, rapid, and chronic (see figure 1) based on how long after exposure to alcohol tolerance develops. Many molecular mechanisms underlie the development of these types of tolerance.
What does it mean to have a reverse tolerance to a medication?
Reverse tolerance, also known as sensitization or behavioral sensitization, occurs when an effect of a drug increases with repeated administration. Reverse tolerance occurs less frequently than tolerance and happens only with particular effects of certain drugs.
What is the difference between tachyphylaxis and tolerance?
The term tachyphylaxis is used to describe desensitization that occurs very rapidly, sometimes with the initial dose. The term tolerance is conventionally used to describe a more gradual loss of response to a drug that occurs over days or weeks.
What drugs cause tachyphylaxis?
Over-the-counter ophthalmic decongestant drops, such as Visine (Pfizer), are another category of drugs that induce tachyphylaxis. In particular, these medications contain alpha-adrenergic amines—such as tetrahydrozoline, naphazoline or phenylephrine—that act as vasoconstrictors.
What are the 6 types of tolerance?
The types of drug tolerance include pharmacokinetic, pharmacodynamic, psychological, behavioral and tachyphylaxis.
What is tolerance in pharmacy?
Tolerance is a person’s diminished response to a drug, which occurs when the drug is used repeatedly and the body adapts to the continued presence of the drug. Resistance refers to the ability of microorganisms or cancer cells to withstand the effects of a drug usually effective against them.
What causes tolerance to drugs?
Usually, tolerance develops because metabolism of the drug speeds up (often because the liver enzymes involved in metabolizing drugs become more active) and because the number of sites (cell receptors) that the drug attaches to or the strength of the bond (affinity) between the receptor and drug decreases (see …
What is the difference between tolerance and sensitization?
In the context of the study of drugs, tolerance refers to the decreased effectiveness of a given drug with repeated administration; sensitization to the increased effectiveness with repeated administration.
What are the types of drug tolerance?
There are two types of drug tolerance: physiological and behavioral. Physical tolerance occurs at the cellular level. The body increases the rate at which the drug is broken down (metabolized).
What are the four types of tolerance?
What does higher tolerance mean?
When you establish a high tolerance to a medication, it means the dosage will need to be increased or that it may be time to switch medicines. Tolerance can also be developed when it comes to alcohol and illicit drugs.
Which drugs cause sensitization?
Most major drugs of abuse are capable of inducing sensitization, including psychostimulants (amphetamine, cocaine, MDMA, cathinone, fencamfamine, methylphenidate, phenylethylamine, etc.), opiates, phencyclidine, alcohol, and nicotine.
What is medication tolerance and how do you develop it?
Medication tolerance, or drug tolerance, occurs when the body gets used to a medication so that either more medication is needed to give the desired effect, or a different medication is needed. Depending on the drug, tolerance can develop acutely, in a manner of days, or chronically, over a number of weeks or months. 1
What is the difference between parallelism tolerance and parallelism axis?
When we apply it to a surface, it controls the parallelism between two planes. Whereas when we apply it to an axis, it controls the parallelelism of an axis is w.r.t. the reference plane. Parallelism Tolerance creates a tolerance zone of two parallel planes parallel to the datum feature or surface.
What is parallelism tolerance in GD?
GD Parallelism Tolerance: Geometric Dimension and Control Parallelism tolerance in gd&t is a type of orientation control tolerance that controls the parallelism of two lines, surfaces, or axis. It does not control the angle of the referenced feature. But it creates a tolerance zone of two parallel planes where all points of the feature must lie.
What does tolerance mean in medical terms?
Understanding Tolerance. Tolerance is defined as the diminishing effect of a medication following repeated administration at a certain dose. It is often a normal adaptive response to ingested drugs, as the body tries to maintain homeostasis or balance.
