Drugs adverse effects

The desired (or intended) principal effect of any drug is to modify body function in such a manner as to alleviate symptoms caused by the patient s illness. In addition, a drug may also cause unwanted effects that can be grouped into minor or side effects and major or adverse effects. These, in turn, may give rise to complaints or illness, or may even cause death. 

Causes of adverse effects over-dosage (A). The drug is administered in a higher dose than is required for the principal effect this directly or indirectly affects other body functions. For instances, morphine (p. 210), given in the appropriate dose, affords excellent pain relief by influencing nociceptive pathways in the CNS. In excessive doses, it inhibits the respiratory center and makes apnea imminent The dose dependence of both effects can be graphed in the form of dose-response curves (DRC). The distance between both DRCs indicates the difference between the therapeutic and toxic doses. This margin of safety indicates the risk of toxicity when standard doses are exceeded. 

No substance as such is toxic In order to assess the risk of toxicity, knowledge is required of 1) the effective dose during exposure 2) the dose level at which damage is likely to occur 3) the duration of exposure. 

The above forms of hypersensitivity must be distinguished from allergies involving the immune system (p. 72). 

Lack of selectivity (C). Despite appropriate dosing and normal sensitivity, undesired effects can occur because the drug does not specifically act on the targeted (diseased) tissue or organ. For instance, the antichoUnergic, atropine, is bound only to acetylcholine receptors of the muscarinic type however, these are present in many different organs. 

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Cardiovascular targets assoicated with adverse drug effects. 

ADVERSE DRUG EFFECTS Information about adverse drug effects of the prescribed drug must be included when die nurse develops a teaching plan for die patient. The nurse should teach the patient the following general points about adverse drug effects ... 

The expected outcomes of the patient may include an optimal response to therapy, which includes control of die infectious process or prophylaxis of bacterial infection, an absence of adverse drug effects, and an understanding of and compliance with die prescribed treatment regimen. 

D Risk for Injury related to sedative or hypnotic effects ot drug Disturbed Sleep Pattern related to adverse drug effects... 

Accurate assessments for the appearance of adverse drug effects assume a greater importance when the patient may not be able to verbalize physical changes to the primaiy health care provider or nurse. 

Q Risk for Imbalanced Fluid Volume related to adverse drug effects of lithium... 

Q Impaired Oral M ucous Mem bran es related to adverse drug effects (dry moufh, nose, and throat)... 

Contact the primary care provider if adverse drug effects occur. 

Some patients experience dizziness or light-headedness, especially during the first few days of therapy or when a rapid diuresis has occurred. Fhtients who are dizzy but are allowed out of bed are assisted by the nurse with ambulatory activities until these adverse drug effects disappear. 

D Risk for Infection related to adverse drug effects D Disturbed Thought Processes related to adverse drug reactions... 

Q Sensory-Perceptual Alteration Impaired Vision related to adverse drug effects or disease condition... 

Adverse drug effects, some of which are preventable. 

What potential adverse drug effects may occur ... 

Institute appropriate pharmacotherapy based on lipid abnormality. Obtain appropriate baseline labs to monitor for adverse drug effects. Assess potential disease and drug interactions that may affect choice or intensity of pharmacotherapy. 

Educate patients on specific adverse drug effects, particularly with metronidazole (avoidance of alcohol) and bismuth (change in stool color). 

Educate the patient on proper use of drug therapy, including when to expect symptom improvement after initiation of treatment and which signs or symptoms to report that might be related to adverse drug effects. 

When sufficient evidence is available to determine that the patient has real seizures and is at risk for another seizure, pharmacotherapy is usually started (Fig. 27-2). The patient should be in agreement with the plan, be willing to take the medication, and be able to monitor seizure frequency and adverse drug effects in some way. Design of an appropriate pharmacotherapeutic plan is based on the patient s seizure type, the common adverse-effect profile of possible AEDs, and economic factors (e.g., cost of the drug, insurance formulary, and ability to pay). Other patient factors such as gender, concomitant drugs, age, and lifestyle also need to be considered. 

The success of treatment is measured by the early termination of seizures, without adverse drug effects or brain injury. Therefore, it is essential to start pharmacologic treatment as soon as possible. First-line treatment for SE should halt seizure activity within minutes of administration. In patients who are unarous-able following treatment, an EEG should be done to rule out continued excessive electrical brain activity and confirm termination of seizures. A physical exam and evaluation of the patient s laboratory results can help determine if the cause or complications of seizure activity are being appropriately treated. 

Evaluate the patient for the presence of adverse drug effects, drug-drug interactions, and drug allergies. 

The primary goals of treatment are correction of the intraabdominal disease processes or injuries that have caused infection and drainage of collections of purulent material (abscess). A secondary objective is to resolve the infection without major organ system complications (e.g., pulmonary, hepatic, cardiovascular, or renal failure) or adverse drug effects. Ideally, the patient should be discharged from the hospital with full function for self-care and routine daily activities. 

Educate the patient on common adverse drug effects and a few of the key signs and symptoms of severe toxicity (i.e., jaundice and abacavir hypersensitivity reaction). Tell them to call their provider immediately if any of those symptoms occur. Make sure they have the correct telephone number for the clinic. 

Laboratory monitoring is of little value in monitoring response to therapy but is essential for detecting and preventing adverse drug effects (see Table 4-2). 

Patients should be questioned about the presence of symptoms that may be related to adverse drug effects (see Table 4-3). 

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