Life threatening reactions

Some texts use both terms side effect and adverse reactions. These texts distinguish between the two terms by using side effects to explain mild, common, and nontoxic reactions adverse reaction is used to describe more severe and life-threatening reactions. For the purposes of this text only the term adverse reaction is used, with the understanding that these reactions may be mild, severe, or life threatening. 

More than half of the patients receiving this drug by the parenteral route experience some adverse reaction. Severe and sometimes life-threatening reactions include leukopenia (low white blood cell count), hypoglycemia (low blood sugar), thrombocytopenia (low platelet count), and hypotension (low blood pressure). Moderate or less severe reactions include changes in some laboratory tests, such as the serum creatinine and liver function tests. Other adverse reactions include anxiety, headache, hypotension, chills, nausea, and anorexia Aerosol administration may result in fatigue a metallic taste in the mouth, shortness of breath, and anorexia... 

If your patients are taking MAOIs, they need to avoid foods containing tyramine. Otherwise they may experience a life-threatening reaction, hypertensive crisis. Be sure to instruct ycur patients to avoid the following foods ... 

Weiss M, Nyhan ED, Peng JK, Horrow JC, Lowen-stein E, Hirshman C, Adkinson NF Jr Association of protamine IgE and IgG antibodies with life-threatening reactions to intravenous protamine. N Engl J Med 1989 320 886-892. 

Severe life-threatening reactions not mediated by IgE, such as Stevens-Johnson syndrome and toxic epidermal necrolysis, are absolute contraindications to testing, desensitization attempts, and readministration. 

It is ironic that possibly the first animal model of relevance to immunotoxicology was reported by Portier and Richet in 1902 [45] in an attempt to induce tolerance to a sea anemone toxin, they accidentally produced a shock reaction in dogs. Since this was not the protective effect they had hoped to produce (phylaxis for protection in Greek), they named the reaction anaphylaxis [46], The irony, of course, is that this serious reaction, mediated by IgE in humans, has proven to be notoriously difficult to predict based on animal studies. This is no trivial issue, since anaphylaxis is a serious, life-threatening reaction associated with exposure to drugs, foods, cosmetic ingredients, and other exogenous substances [47],... 

Chemotherapy used to treat cancer is toxic by almost anyone s standards. How would it affect someone like Peggy, who experiences life-threatening reactions to even low-level chemical exposures There are no answers. Peggy believes chemotherapy or surgery could be fatal for her, because her lungs burn and airways can close even from exposure to fragrances and other ordinary products. She has chosen to treat her cancer with a non-chemical, non-invasive alternative program, and her trust in God. 

Symptoms can range from mild to disabling and can even be life threatening. Reactions may vary depending upon the person s general state of health and the amount of other recent exposures. The onset of symptoms following an exposure may be immediate or delayed for hours or even days, and quite often are masked by the effects of ongoing exposures. Symptoms can last from a few seconds to a few weeks or months. Some people experience distinctly different constellations of symptoms in response to different substances. New symptoms may develop over time, and some may resolve. People with moderate to severe cases of MCS may be partially or totally disabled for several years or for life. Many improve but full recovery is rare. 

Most inhibitors of aldehyde dehydrogenase are inhibitors because they react with the thiol group at the active site of the enzyme. Inhibitors such as disulfiram (Fig. 4.31) have been used in the treatment of alcoholism because if someone drinks alcohol while taking the inhibitor, there is a buildup of acetaldehyde, which causes many unpleasant symptoms such as flushing and nausea (77,78). However, if someone drinks a large amount of alcohol while taking disulfiram it can lead to a life-threatening reaction. 

Time Frames. The time period for submitting written IND safety reports has been revised from ten working days to 15 calendar days. For telephone reports (fatal and life-threatening unexpected reactions), it has been revised from three working days to seven calendar days. Such reports can also be made by fax. Telephone reporting was previously restricted to clinical studies conducted under the IND, but under the new rule, telephone reporting within seven calendar days applies to any unexpected fatal or life-threatening reaction from any source. 

In addition to diseases of important organs such as the lungs, the liver, and the kidneys, hereditary or acquired characteristics such as immunodeficiency and hypersensitivity may also influence sensitivity to xenobiotics. For example, atopies (individuals with immunologically mediated allergy) may develop life-threatening reactions to a chemical at an exposure level that is insignificant for the population in general (KEMI 2003). 

Aprepitant is a moderate CYP3A4 inhibitor. Aprepitant should not be used concurrently with pimozide or cisapride. Inhibition of cytochrome P450 isoenzyme 3A4 (CYP3A4) by aprepitant could result in elevated plasma concentrations of these drugs, potentially causing serious or life-threatening reactions. Aprepitant is contraindicated in patients who are hypersensitive to any component of the product. 

Do not administer ritonavir concurrently with any of the following listed drugs because of the potential for serious or life-threatening reactions such as cardiac arrhythmias, prolonged or increased sedation, and respiratory depression ... 

Injection - 244 of 424 (57.5%) patients treated with pentamidine injection developed some adverse reaction. Most of the patients had acquired immunodeficiency syndrome (AIDS). In the following, severe refers to life-threatening reactions or reactions that required immediate corrective measures and led to discontinuation of pentamidine. 

Many different symptoms can occur during IgE-mediated food allergies including cutaneous, gastrointestinal, respiratory, and sometimes cardiovascular symptoms (Table 4.3). Reactions can sometimes be fairly mild, but severe and life-threatening reactions involving symptoms such as lar)mgeal edema, asthma, and anaphylactic shock can occur on occasion. 

Procaine penicillin modestly extends the duration of action of benzylpenicillin. The dose is limited by the volume that can be administered intramuscularly. If the insoluble penicillins are by accident injected intravenously potentially life-threatening reactions can result. 

Thiopentone administration is associated with a threefold increase in circulating histamine concentrations. Hypersensitivity reactions range from cutaneous rashes to severe or fatal anaphylactic reactions. The incidence of life-threatening reactions is 1 14000-1 20000. 

Aiiergic reactions. Skin rashes have been reported. Life-threatening reactions are no more common than with thiopentone. 

Intraocular pressure is slightly increased by ketamine. Uterine tone and intrauterine pressure are increased in both the non-pregnant and pregnant uterus, effects that may be harmful in abruptio placentae and cord prolapse. Ketamine rapidly crosses the placenta and equilibrates in fetal plasma. Transient rashes have been reported in 20% of patients although life-threatening reactions are rare. Indications... 

Hyperpyrexia and hypertension have been observed with the use of pethidine and MAO inhibitors. Pethidine is the opioid most commonly associated with an adverse reaction with MAOIs. Although only a small proportion of patients taking MAOIs will react adversely to pethidine, there is no sure way of predicting those in whom the combination could produce severe, life-threatening reactions. These can present in two distinct forms. The excitatory form is characterised by sudden agitation, delirium, headache, hypotension or hypertension, rigidity, hyperpyrexia, convulsions and coma. It is possibly caused by an increase in cerebral 5-HT concentrations due to inhibition of MAO. This is potentiated by pethidine, which blocks neuronal uptake of 5-HT. The depressive form, which is frequently severe and fatal, presents as respiratoiy and cardiovascular depression and coma. It is the result of a reduced breakdown of pethidine due to the inhibition of hepatic /V-demethylase by MAOIs, leading to accumulation of pethidine. The risk of adverse reactions to pethidine may be less likely with the newer, specific MAO-A inhibitors. Interactions with other opioids, such as morphine and pentazocine, have been reported, but are less common. Other opioids appear to be safe in combination with MAOIs, with the possible exception of phenoperidine, which is metabolised to pethidine, norpethidine and pethidinic acid. 

The majority of clinically definite and immunologically confirmed reactions have erythema as a main feature. Erythema is, however, a common accompaniment to the administration of many drugs, often as a result of directly mediated histamine release, and it should not be regarded as part of a life-threatening reaction unless there are changes in other systems of the body. In addition, most reactors have oedema, particularly of the eyelids. 

The pharmacokinetics of saquinavir is modified by agents that alter isoenzyme CYP3A4 of the cytochrome P-450 system and P-glycoprotein transporter. It should not be administered with midazolam, triazolam and ergot derivatives. The plasma concentrations of saquinavir are lower when coadministered with efavirenz, nevirapine or rifampin. Ritonavir reverses the effects of nevirapine on saquinavir. The coadministration of astemizole, terfenadine, amiodarone, bepridil, quinidine, propafenone or flecainide with saquinavir is also not recommended due to its potential for serious and/or life-threatening reactions. 

Taken in combination with certain other drugs, alcohol can cause life-threatening reactions. 

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