Question: How Does PH Affect Drug Stability?

What factors affect the stability of a drug?

The degradation of drugs and drug metabolites in samples can occur through either reversible or irreversible processes.

Common factors that affect this stability include temperature, light, pH, oxidation and enzymatic degradation..

How does pH affect precipitation?

Selective Precipitation Using pH In this technique, pH is often used to control the concentration of the anion in solution, which controls which cations precipitate. The concentration of anions in solution can often be controlled by adjusting the pH, thereby allowing the selective precipitation of cations.

How suspension improves the stability of drugs?

There are some useful methods to improve the physical stability of a suspension, such as decreasing the salt concentration, addition of additives to regulate the osmolarity, as well as changes in excipient concentrations, unit operations in the process, origin and synthesis of the drug substance, polymorphic behavior …

Why is stability testing important?

Stability testing provides evidence on how the quality of a drug substance or product varies over a given time period and under the influence of environmental factors including temperature, humidity and light.

How does pH affect drug solubility?

Increase in pH led to decrease in solubility and percentage of unionized form of weakly basic drug and an increase in its distribution coefficient. … The increase in unionized form of the drug increased the permeability of the drug through the skin.

Why are drugs stable at pH 2?

Acidic and alkaline pH influence the rate of decomposition of most drugs. … It will increase stability by: – suppressing ionization – reducing the extreme pH required to achieve solubility – enhancing solubility and – reducing the water activity by reducing the polarity of the solvent.

How does temperature affect drug stability?

When a drug is stored in temperatures that are too high or too low, the drug’s chemical stability will likely be impacted. That means that the drug may degrade and form impurities. While these impurities may not be visually noticeable, this degradation can cause real problems when the drug is administered.

Which form of drug has highest solubility?

11. Which form of a drug has greater solubility? Explanation: Anhydrous form of a drug has a greater aqueous solubility than the hydrates. This is because the hydrates are already in interaction with the water and therefore have less energy for crystal breakup.

Why is mannitol used in chewable tablets?

Mannitol is widely used as an excipient in chewable tablet for its non-hygroscopic nature for moisture sensitive drugs. As we know difficulty in swallowing (Dysphasia) is common among all age groups, especially in elderly and in also seen of swallowing of conventional tablets and capsules.

What are the three types of stability?

There are three types of stability.Stable equilibrium.Unstable equilibrium.Neutral equilibrium.

What are the three principles of stability?

Increase base of support. Lower the center of gravity. Keep center of gravity within base of support.

What is the stability of a drug?

The term drug stability refers to the extent to which a drug substance or product retains, within specified limits and throughout its period of storage and use, the same properties and characteristics that it possessed at the time of its manufacture.

How does moisture affect stability of drugs?

It has long been known that moisture affects the stability of some drug substances. Even though the water is driven off in a wet granulation, there is still sufficient moisture stress in the process to induce excessive decomposition on subsequent storage. …

What are the factors of stability?

For maximum stability the line of gravity should intersect the base of support at a point that will allow the greatest range of movement within the area of the base in the direction of the forces causing motion. IV. Other things being equal, the greater the mass of a body, the greater will be its stability. V.

How does pH affect lipid solubility?

A substance will become more lipid soluble in a solution with a pH similar to its own pH. A weak base is more lipid-soluble in an alkaline solution. A weak base is more WATER-soluble in an acidic solution.

What are the stability zones and stability conditions?

Long Term Stability Testing ConditionsClimatic ZoneTemperatureHumidityZone II25ºC ± 2ºC60% RH ± 5% RHZone III30ºC ± 2ºC35% RH ± 5% RHZone IVa30ºC ± 2ºC65% RH ± 5% RHZone IVb30ºC ± 2ºC75% RH ± 5% RH3 more rows

What is the importance of determining the moisture content of drugs?

Moisture content determination is important, not only to know excess water, but also in conjunction with suitable temperature moisture will lead to the activation of enzymes and gives suitable conditions to the proliferation of living organism.

What factors affect balance and stability?

Factors Increasing StabilityCenter of gravity falls within base of support. … Larger base.Greater weight.Lower center of gravity.When anticipating an oncoming force. … Greater friction between body and surfaces it contacts.Rotation about axis. … Kinesthetic physiological functions.