Unwanted effects and adverse drug reactions

Cur d yesterday of my disease I died last night of my physician.  

Nature is neutral, i.e. it has no intentions towards humans, though it is often unfavourable to them. It is mankind, in its desire to avoid suffering and death, that decides that some of the biological effects of drugs are desirable (therapeutic) and others are undesirable (adverse). In addition to this arbitrary division, which has no fundamental biological basis, 

There is general agreement that drugs prescribed for disease are themselves the cause of a serious amount of disease (adverse reactions), ranging from mere inconvenience to permanent disability and death. 

Since drugs are intended to relieve suffering, patients find it peculiarly offensive that they can also cause disease (especially if they are not forewarned). Therefore it is important to know how much disease they do cause and why they cause it, so that preventive measures can be taken. 

It is not enough to measure the incidence of adverse reactions to drugs, their nature and their severity, though accurate data are obviously useful. It is necessary to take, or to try to take, into account which effects are avoidable (by skilled choice and use) and which are unavoidable (inherent in drug or patient). Also, different adverse effects can matter to a different degree to different people. 

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An adverse reaction is any reaction to a drug that is harmful to the patient. Side effects, unwanted effects and adverse effects are all adverse reactions some are considered to be less serious than others, although the terms are used synonymously. 

For drugs already on the market, the discovery of inherited variants2 utilizes two unwanted effects of drugs adverse drug reactions (ADRs) and therapeutic failures. 

These adverse drug reactions are generally dose-related and most can be predicted. They can be caused by an exaggeration of a drug s intended pharmacological effect or by an unwanted action or side effect. Type A adverse reactions are most likely to occur with drugs that have a steep dose-response curve (see Figure 3.1) and/or small therapeutic ratio (TR). 

Adverse drug reactions. Proven unwanted side-effects due to treatment with a drug. They are conventionally classified into two sorts. Type A, which are due to a predictable pharmacological effect of the drug and are usually dose-dependent, and Type B, which are unpredictable (perhaps allergic) and are usually more serious and rarer. 

Both guidelines are based on a single compound approach for risk assessment, which implies some shortcomings. In real world situations there is always a mixture of several compounds (parent compounds, other chemicals and transformation products thereof). As known from pharmacy, the risk of unwanted side effects increases with the number of active compounds taken at the same time (polypharmacy). There are several concerns about polypharmacy, such as increased adverse drug reactions and drug-drug interactions. ... 

During the last four decades, microfilaricidal diethylcarbamazine [46] and macrofilaricidal suramin [47,48] have been used for the treatment of filariasis however, iboth of these drugs possess unwanted side-effects such as mazzotti reaction, toxicity, etc. Suramin is highly active against the adult worm of 0. volvulus [47] in humans, but it is very toxic to the kidney, liver and bone marrow and has other side-effects similar to DEC. DEC in the treatment of onchocerciasis produces severe mazzotti reaction (an allergic response due to rapid death of microfilariae) along with other side-effects such as pruritus and anaphylactic shock. However, the mass treatment of lymphatic filariasis with DEC was successful due to a lower and milder incidence of these adverse... 

Neuroleptic drugs can produce a variety of adverse effects in several organ systems. Extrapyramidal reactions and sedation are common less common are seizures, unwanted behavioral effects, and tardive dyskinesia. Most neuroleptic drugs have anticholinergic effects and commonly produce dry mouth, blurred vision, and constipation. Postural hypotension is common. These effects usually disappear when the drug is stopped or the dosage is reduced. 

Data are available on the incidence of adverse effects of this drug (1-3). A review of published studies showed that about 13-15% of patients have adverse effects. The withdrawal rate because of unwanted reactions was 3.2-12% in short-term studies and 4% in one long-term trial. Adverse effects involved the gastrointestinal tract in 8-12% of patients, the central nervous system in 1-10% and the skin (rash, sweating, and itching) in 1-4%. Cutaneous photosensitivity and edema have also been reported. 

In medicinal use, drugs are usually administered with the best of intentions, which is to have a beneficial therapeutic effect. However, all drugs have the potential to cause unwanted effects too, and these range from being minor or trivial to being life threatening. Unwanted effects are known as adverse reactions or side effects and can occur by a variety of mechanisms. It is important for health care professionals to be aware of potential adverse effects of drugs and to know how to report new ones when they occur. 

De Groot AC, Frosch PJ (1997) Adverse reactions to fragrances. A clinical review. Contact Dermatitis 36 57-86 De Groot AC, Weyland JW, Nater JP (eds) (1994) Contact allergy to fragrance materials. In Unwanted effects of cosmetics and drugs used in dermatology, 3rd edn. Elsevier, Amsterdam, Chap. 5.8-5.15, pp 65-72... 

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