In drug-drug interactions, one drug affects the activity of another, usually when both are administered together. Such interactions may result in decreased or increased activity of one or both drugs. While many forms of drug-drug interactions exist, most can be broadly classified into interactions that involve the trip of a drug once administered or the action of a drug on the body.
Drug-drug interactions that affect the travel of drugs in the body can be further understood as those that affect absorption into the bloodstream, distribution within the body, breakdown into various products, or removal from the body.
Absorption interactions can occur when particles of one drug have a large enough surface area to allow particles of the other drug to stick to them, the two drugs can also bind to each other, or when one drug is exposed to the acidity of stomach contents or that Alters the rate at which the stomach moves its contents.
These interactions may alter the ability of one or both drugs to enter the bloodstream. When one drug only decreases the rate of absorption of the other, a patient is usually unaffected on regular use of both drugs. However, if one drug reduces the extent of absorption of another, the patient may be exposed to lower levels of the other drug than necessary and the other drug may be ineffective in treatment.
Delivery interactions can occur when the drugs reach the bloodstream and tissues. Competition may arise between two drugs to bind to the same protein in the blood, or one drug may remove the other from its affinity with tissues. In the second instance, it is more common when one drug displaces another from tissues, to find that the displaced drug accumulates in the blood putting the affected patient at greater risk of experiencing toxicity. An example is when the heart medicines quinidine and Lanoxin are taken together, digoxin blood levels may increase and the patient may have adverse effects if not monitored appropriately.
While drugs can be broken down in many different places in the body, the most common site is the liver. Here, a system of enzymes may be up-regulated or down-regulated by one drug resulting in the rapid or slow breakdown of another, respectively. Examples of drugs that regulate specific enzymes in the liver include the anti-epileptic Dilantin (phenytoin) and Tegretol. The enzyme up-regulation effect usually occurs gradually with maximum effect in 7 to 10 days after starting the drug. It may take the same or longer time to return to normal when the drug is discontinued. Examples of drugs that control specific enzymes in the liver include the antibiotics erythromycin and ciprofloxacin.
Most perishable pharmaceutical products, as well as whole drugs, are removed from the body through urine. When one drug affects the pH of urine, it can affect the ability of the other drug to enter the urine, depending on how it changes during the filtering process in the kidneys. Transporter molecules in the kidney that facilitate drug removal may be more or less available to one drug as a result of the presence of another drug.
In this article, we have done about drug injection and drugs, hope you liked this article. If you are suffering from any kind of drug addiction and want to get your treatment done from a Nasha Mukti Kendra in Punjab, then before choosing any center you should know about it thoroughly and then start your treatment.