Changes

Some drugs may display zero-order kinetics, i.e. the rate of metabolism of the drug is constant and does not vary with dose. This is the case for phenylbutazone in the dog and salicylate in the cat.

Some drugs may display zero-order kinetics, i.e. the rate of metabolism of the drug is constant and does not vary with dose. This is the case for phenylbutazone in the dog and salicylate in the cat.

NSAIDs may be administered orally or parentally. As they are weak acids, NSAIDs are well absorbed following oral administration. The presence of food may, however, interfere with this absorption. Once absorbed, NSAIDs have a small apparent volume of distribution. In actuality, the magnitude is not that small; the drugs accumulate at sites of inflammation due to plasma protein escaping through leaky blood vessels in these locations. This is a good property - the drug reaches the areas where it is needed most.

NSAIDs may be administered orally or parentally. As they are weak acids, NSAIDs are well absorbed from the stomach following oral administration. The presence of food may, however, interfere with this absorption. Once absorbed, NSAIDs have a small apparent volume of distribution. In actuality, the magnitude is not that small; the drugs accumulate at sites of inflammation due to plasma protein escaping through leaky blood vessels in these locations. This is a good property - the drug reaches the areas where it is needed most.

The half-life of NSAIDs is often short, and so dosing is required every 4 to 6 hours. Despite this, the duration of action is quite long: although the drug leaves the plasma rapidly it remains bound to the COX enzyme for more extended periods.

The half-life of NSAIDs is often short, and so dosing is required every 4 to 6 hours. Despite this, the duration of action is quite long: although the drug leaves the plasma rapidly it remains bound to the COX enzyme for more extended periods.