Combination therapy is the opposite of monotherapy and refers to a treatment pathway that simultaneously includes several different therapeutic directions or active agents in order to be able to act against several factors of a disease at the same time. Combination therapy plays a particularly important role in the treatment of HIV patients. In this case, we are talking about a highly active antiretroviral therapy that stops the viruses from multiplying, thus preventing or at least delaying the progression of the disease and thus prolonging the patient’s life. Combination therapies are usually associated with a much higher rate of side effects than monotherapies, and the individual agents must be thoroughly tested in advance for their interactions and general combinability.
What is combination therapy?
Combination therapy is a form of treatment that follows more than one therapeutic principle at a time. It usually involves drug treatments that focus on more than one active ingredient. In medicine, combination therapy is a form of treatment that follows more than one therapeutic principle at the same time. In most cases, these are drug treatments that target more than one active ingredient. This type of drug administration may encompass two different drugs or correspond to a combination drug that carries more than one active ingredient. The opposite of this type of treatment is called monotherapy and is limited to one active ingredient. Combination therapies can be differentiated into several subtypes. The best known are triple and quadruple therapy. While triple therapy involves the use of three drugs, quadruple therapy involves the use of four drugs. For the first group, Helicobacter pylori eradication to eliminate the Helicobacter bacterium as completely as possible is one of the best-known examples. In addition, life-prolonging HIV therapy is sometimes a triple and sometimes even a quadruple therapy. The biggest advantage of any combination therapy is the simultaneous effect on different disease parameters. On the other hand, compared with monotherapy, the major disadvantage is the usually high side effects of this form of treatment.
Function, effect, and goals
With a combination therapy, several factors of a disease can be positively influenced simultaneously. Which drugs can be combined in the course of such a measure is decided by the respective disease, but the interactions and side effects of the individual drugs are also important here. In current medicine, combination therapy plays a role in particular in the treatment of HIV patients. The most effective form of treatment in the fight against the HIV virus currently corresponds to highly active antiretroviral therapy, which relies on at least three different drugs. All three drugs contain antiretroviral, or virus-blocking, agents. Typically, two nucleoside reverse transcriptase inhibitors are used and combined together with a non-nucleoside reverse transcriptase inhibitor or protease inhibitors. Often, the efficacy of the latter is additionally raised via boosting. This combination can limit viral replication to such an extent that HIV can henceforth no longer be detected directly and patients’ lives can be prolonged by a lasting, if not always complete, restoration of immune functions. Many typical symptoms of HIV recede in the course of therapy and the risk of progression of the disease is minimized. Similar to this combination therapy, three different drugs are used for Helicobacter pyori eradication. Usually, amoxicillin is combined with clarithromycin and proton pump inhibitors in the course of this measure, but the combination of amoxicillin, metronidazole and proton pump inhibitors is also conceivable. A third route is the simultaneous administration of metronidazole, clarithromycin, and proton pump inhibitors. In addition to these combination therapies, combination therapies are also often used, for example, for epilepsy, blood pressure disorders, or type II diabetes. However, combination therapies can also prove useful for conditions such as hepatitis C, ADHD, cardiac arrhythmias and complex tumors.As a rule, the more complex and multifaceted the disease, the more sensible it is to use a form of therapy with several active ingredients, since complex diseases in particular usually involve many different factors that cannot usually be adequately countered by a single active ingredient.
Risks, side effects, and hazards
Any combination therapy should only be performed with close attention to drug interactions. In addition, side effects are often significantly higher for combination therapies than for monotherapies. Therefore, the treating physician must determine the benefit/risk ratio for the individual case together with the patient in advance. In the case of triple therapy for HIV patients, for example, the benefits are usually significantly higher than the risks. Most patients tolerate the therapy method, which has been available since 1996, extremely well over many years. Nevertheless, side effects such as bloating, vomiting or diarrhea can occur for this treatment route. A slight increase in liver values can also occur, as the drugs sometimes have inherent liver-toxic properties, although these only cause actual liver damage in extremely rare cases. Renal dysfunction is also conceivable, and neuropathies, sleep disturbances, and nightmares may occur in the course of treatment. Allergies and fat distribution disorders are among the most common side effects. The list of these side effects cannot, of course, be transferred to combination therapies for other diseases, which involve entirely different active ingredients and thus have effects on the body. The list is therefore only intended as an illustration of the generally increased side effects associated with combination therapies. Especially when a combination therapy is used over a longer period of time, patients often develop resistance to one of the active ingredients used. Therefore, research is permanently underway, and for each combination therapy route, to find other agents that can be combined without risk.
