A drug-drug interaction involves 1 drug affecting the activity of one other frequently when both are concurrently administered. Such associations can easily cause the reduced or perhaps enhanced activity of one or both drugs. While many forms of drug-drug associations exist, most may end up being broadly classified into interactions that involve the travel of those drug once administered (pharmacokinetic) or even the action of the drug on your body (pharmacodynamic).
Drug-drug interactions which affect the travel of drugs in the body may become further understood as those that affect absorption into the bloodstream, distribution within your body, breakdown into different products or perhaps removal with the body.
Absorption interactions may come up when 1 drug's particles just have a large enough surface area to trigger another drug's particles to stick to them, both drugs can also bind to each other, or even one drug affects the acidity of the stomach contents or even the rate at which the stomach moves it's contents. These kinds of interactions can change the ability of 1 or perhaps both drugs to get into the bloodstream. When a drug only reduces the rate of absorption of one other, a sick person on regular use of both drugs is frequently unaffected. However, if a single drug reduces the extent of absorption of these other, the patient can easily be exposed to lower levels of the 2nd drug than required and the second drug can hence become ineffective in treatment.
Distribution interactions can come up when drugs reach the bloodstream and the tissues. Competition between two drugs can occur with regard to binding for the same proteins in the blood or perhaps one drug may dislodge another from it's connection with tissues. It is more common in the second instance when one drug displaces another from the tissues, to find which the displaced drug accumulates in the blood leading to a greater risk of an affected sick person experiencing toxicity. An example is when the heart medications quinidine and Lanoxin® (digoxin) are taken concurrently, digoxin blood levels can easily rise and negatively affect the patient if not monitored appropriately.
While drugs may end up being broken down at many different sites in the body, the most common site is the liver. Here, a system of enzymes may become up-regulated or even down-regulated by 1 drug to trigger the quicker or even slower breakdown of those other respectively. Examples of drugs that up-regulate specific enzymes in the liver, include the anti-epileptics Dilantin® (phenytoin) and Tegretol® (carbamazepine). The enzyme up-regulation response frequently occurs gradually with maximal effects observed in seven to 10 days of starting the drug. It may also take an equal or even longer moment before normalcy is regained upon discontinuing the drug. Examples of drugs which down-regulate particular enzymes in the liver, include the antibiotics erythromycin and ciprofloxacin. The onset of enzyme down-regulation is often faster as compared to up-regulation.
The majority of broken down drug products as properly as whole drugs are removed of the body through the passing of urine. When one drug changes the pH of these urine, this particular can affect another drug's ability to get into the urine pending on how it's form affects during the filtering process in the kidneys. Transporter molecules in the kidney which facilitate drug removal can also be more or even less available to one drug being a result of the presence of another.
Drugs can also interact and exert a net reaction by their direct routines on your body. Two drugs with comparable effects when administered together can show synergism in action event though acting at different sites or receptors in our bodies. An example is the drowsiness which can end up being experienced when a sedative such as Valium® (diazepam) is taken concurrently with an antihistamine just similar to Polaramine® (dexchlorpheniramine). Conversely when two drugs that simply have opposing effects are taken concurrently, the reaction to either or even both may be reduced. An example is the opposing wakefulness and drowsiness which can easily result from consuming a caffeine-based anti-migraine preparation and a sedative.
Another set of action-related drug-drug associations occurs when 2 drugs exert toxicity towards the same organ or even tissue in your body. Concurrent administration of those 2 drugs may cause damage for the corresponding organ or tissue despite the individual dose of each drug alone not being enough to trigger toxicity under typical circumstances. The common organs that are most often affected by such drug-drug toxicity associations are the kidneys and the liver. Of note is also which one drug can grow up the organ-toxic response of another even though it does not exert any direct toxicity towards which organ by itself.
Because of these numerous drugs available and the many more which are all the time arriving, drug-drug relationships may become quite common. Yet, the adverse effects can easily become minimized through consultation with an experienced medication expert. When such interactions are anticipated early, the most appropriate countermeasures may end up being readied to help keep well being.