A contraindication occurs when the attending physician recognizes that a condition, disease or situation prohibits the use of therapeutic or medical measures on the patient. In this case, the presence of the contraindication prevents the achievement of a positive treatment goal.

In the case of absolute contraindications , doctors are forced to abandon a planned measure, since it negatively affects the patient’s state of health. If there is a relative contraindication , the physicians carry out the planned therapeutic measure if the expected benefit outweighs the feared damage to health. Before starting this measure, the doctors carefully assess the risk-benefit ratio.

In most cases, pregnancy is an absolute contraindication, as many medications and therapeutic measures should not be administered during this period in order to prevent prenatal damage to the embryo.

Function, effect & goals

There are many reasons for the existence of a contraindication. Some medicines are too strong or too weak under certain conditions. The well-known pain reliever acetylsalicylic acid can cause stomach upset as a possible side effect. In the majority of patients, taking this painkiller over a short period of time is harmless.

In patients with gastric ulcers , the gastric symptoms may worsen. Stomach ulcers are therefore a contraindication for this drug. Some contraindications must be strictly adhered to (absolute contraindication), others give the physicians room to maneuver (relative contraindication). An absolute case exists when the administration of medication to the patient has such serious side effects that its use should be avoided under all circumstances.

When using acetylsalicylic acid, in addition to gastric ulcers, a pathologically increased tendency to bleed or the last third of a pregnancy (3rd trimester) are absolute contraindications. This is also the case in the event of an allergic shock reaction to the administration of penicillin . A patient who has once had an allergic reaction to the administration of this drug must no longer take it. In the case of a relative indication, the doctor decides individually in each case whether administering medication is appropriate or not and whether the expected benefit is greater than the health risk associated with the indication.

Relative contraindications when administering acetylsalicylic acid are the first and second trimester of pregnancy (1st and 2nd trimester), children and adolescents under the age of 16 and bronchial asthma . Cardiologists successfully use beta-blockers in the case of coronary heart disease ( angina pectoris ) and high blood pressure . A side effect of beta blockers is the spasm of the bronchial muscles . If a heart patient also suffers from asthma and is given beta blockers, there is a high probability that he will suffer from shortness of breath and the risk of suffocation is high. In this case there is an absolute contraindication.

In heart patients without asthma, on the other hand, the administration of beta-blockers is usually harmless (relative contraindication). Specialist information shows these contraindications under the headings “Interactions with other medicinal products and other forms of interaction”, “Special warnings”, “Precautions for use” and “Fertility, pregnancy and lactation”. Each drug comes with a leaflet that patients must read carefully before taking it. This is especially true for over-the-counter preparations such as dietary supplements and other apparently harmless medicines. All contraindications in the form of side effects and interactions with other drugs are listed on the package leaflet.

Users take these medicines and dietary supplements without medical advice. In case of uncertainty, obtaining medical advice from a doctor or pharmacist is necessary. There are certain circumstances that are mistaken for a contraindication. These “false contraindications” often appear in connection with the implementation of vaccinations . Lay people are more afraid of the possible side effects than of the damage that may occur if the symptoms of the disease are not treated. Long package inserts for the drugs listing possible side effects increase anxiety without naming the risk of non-treatment.

Responsible physicians always weigh the risks of an indicated therapy against the risks of not treating it. Patients cannot conclusively assess contraindications and interactions of individual drugs. This knowledge belongs in the pharmacological part of medical studies. Corresponding lists give the physicians a comprehensive overview of contraindications and interactions. Before the treatment, the doctors ask about intolerances, allergies and previous illnesses in order to rule out contraindications when prescribing medication and interactions. Pharmacists use computer lists to compare prescription drugs before they are given to patients. This double check increases the safety of the therapy.

Risks, side effects & dangers

With age, the risks associated with contraindications increase, since in many cases older people suffer from several diseases at the same time, for which they take different medications.

With increasing age, organs such as the kidneys and liver break down the harmful substances of various medicines more slowly due to a slower metabolism . If patients take several medications at the same time to treat the typical signs of aging such as cardiac insufficiency , diabetes mellitus , high blood pressure and pain caused by wear and tear, it becomes increasingly complicated for physicians to take this situation into account and use all medications in accordance with the guidelines and as standard.

Not only the contraindications in the form of interactions of the individual drugs make the treatment more difficult, but also side effects that may require the use of other drugs. Such a complicated situation, which many elderly people face, requires an examination by a specialist and general practitioner. The situation is ideal when the patient and doctor have known each other for a long time in order to work out the optimal medication for the complicated disease situation. In this way, the doctor is able to assess which medication the patient can possibly do without.

Furthermore, the risk is reduced by taking the medication far apart. The doctor critically questions the usual treatment guidelines and considers which medications absolutely have to be prescribed and which do not.