side effect
Quick Summary
A "side effect" is a secondary and usually adverse or unwanted effect of a medicine. These effects can range from minor, like dizziness or skin reactions, to severe and potentially fatal.12
Adverse drug reactions are generally categorized into two types:
* Dose-dependent: These occur when a drug is taken in a high enough dose. Factors like age, heredity, or existing diseases can influence how an individual responds to a specific dose. For example, Tylenol can cause liver toxicity with heavy, long-term use.34
* Dose-independent: These are less common and are often due to allergic reactions to the drug or its ingredients. They can manifest as mild symptoms or severe, life-threatening issues like respiratory difficulties.3
Some drugs, particularly psychotropic medications used to treat conditions like anxiety and depression, can have a variety of side effects. These can include dependence, withdrawal symptoms, sleepiness, tremors, and in some cases, more serious issues like heart problems or stroke. It's important to note that no drug is entirely without risk, and adverse effects can sometimes be unpredictable.52
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cancerRadiation therapyThe undesirable effects of radiation therapy are divided into acute and late effects. Acute effects occur in rapidly renewing tissues, such as the linings of the oral cavity, the pharynx, the intestine, the urinary bladder, and the vagina. Late effects, which are related to the total dose…
Read MoreThe undesirable effects of radiation therapy are divided into acute and late effects. Acute effects occur in rapidly renewing tissues, such as the linings of the oral cavity, the pharynx, the intestine, the urinary bladder, and the vagina. Late effects, which are related to the total dose…
Read More- cancerChemotherapy
The side effects of chemotherapy vary greatly among individuals and among drug combinations. Side effects arise because many chemotherapeutic agents kill healthy cells as well as cancer cells. Nausea, vomiting, diarrhea, hair loss, anemia, loss of ability to fight infection, and a greater propensity to bleed…
Read MoreThe side effects of chemotherapy vary greatly among individuals and among drug combinations. Side effects arise because many chemotherapeutic agents kill healthy cells as well as cancer cells. Nausea, vomiting, diarrhea, hair loss, anemia, loss of ability to fight infection, and a greater propensity to bleed…
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anticancer drugSide effects…in reducing the severity of side effects associated with the drugs’ use. Indeed, because cancer cells are similar to normal human cells, anticancer agents are generally toxic to normal cells and can cause numerous side effects, some of which are life-threatening. Such side effects include hair loss, sores in the…
Read More…in reducing the severity of side effects associated with the drugs’ use. Indeed, because cancer cells are similar to normal human cells, anticancer agents are generally toxic to normal cells and can cause numerous side effects, some of which are life-threatening. Such side effects include hair loss, sores in the…
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bladder cancerTreatmentThe side effects of radiation treatment may include vomiting, diarrhea, fatigue, or skin irritations resembling a sunburn.
Read MoreThe side effects of radiation treatment may include vomiting, diarrhea, fatigue, or skin irritations resembling a sunburn.
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brain cancerTreatment…localized, however, radiotherapy can cause side effects such as vomiting, diarrhea, or skin irritation. Radiation to the brain may cause scar tissue to form and potentially cause future problems. Memory loss may also occur.
Read More…localized, however, radiotherapy can cause side effects such as vomiting, diarrhea, or skin irritation. Radiation to the brain may cause scar tissue to form and potentially cause future problems. Memory loss may also occur.
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breast cancerTreatmentSide effects of radiation include swelling or thickening of the breast, vomiting, fatigue, diarrhea, and skin irritations resembling sunburn. Chemotherapy, the use of chemicals to destroy cancerous cells, is commonly employed. Chemotherapeutic agents also attack normal cells to some degree, causing side effects that include…
Read MoreSide effects of radiation include swelling or thickening of the breast, vomiting, fatigue, diarrhea, and skin irritations resembling sunburn. Chemotherapy, the use of chemicals to destroy cancerous cells, is commonly employed. Chemotherapeutic agents also attack normal cells to some degree, causing side effects that include…
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cervical cancerTreatmentIn addition to the side effects normally associated with radiation treatment, pelvic radiation therapy may also cause premature menopause, bladder irritation, or a narrowing of the vagina due to scar tissue buildup.
Read MoreIn addition to the side effects normally associated with radiation treatment, pelvic radiation therapy may also cause premature menopause, bladder irritation, or a narrowing of the vagina due to scar tissue buildup.
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esophageal cancerTreatmentThe side effects of radiation treatment include vomiting, diarrhea, fatigue, and esophageal irritation. Chemotherapy is also used for some esophageal cancers. It is not curative, but it can relieve some symptoms and may be able to shrink tumors prior to surgery. Side effects resemble those of…
Read MoreThe side effects of radiation treatment include vomiting, diarrhea, fatigue, and esophageal irritation. Chemotherapy is also used for some esophageal cancers. It is not curative, but it can relieve some symptoms and may be able to shrink tumors prior to surgery. Side effects resemble those of…
Read More- lung cancerTreatment
Side effects include vomiting, diarrhea, fatigue, or additional damage to the lungs. Chemotherapy uses chemicals to destroy cancerous cells, but these chemicals also attack normal cells to varying degrees, causing side effects that are similar to radiation therapy. An experimental technology that has shown promise…
Read MoreSide effects include vomiting, diarrhea, fatigue, or additional damage to the lungs. Chemotherapy uses chemicals to destroy cancerous cells, but these chemicals also attack normal cells to varying degrees, causing side effects that are similar to radiation therapy. An experimental technology that has shown promise…
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therapeuticsCough…almost equal effectiveness but fewer side effects. Most cough preparations containing dextromethorphan also contain a decongestant and an expectorant. Because coughing is an important defense mechanism in clearing secretions from blocked airways, a productive cough (one that produces secretions) should not be suppressed.
Read More…almost equal effectiveness but fewer side effects. Most cough preparations containing dextromethorphan also contain a decongestant and an expectorant. Because coughing is an important defense mechanism in clearing secretions from blocked airways, a productive cough (one that produces secretions) should not be suppressed.
Read More- therapeuticsPrinciples of drug uptake and distribution
…average doses, and they experience side effects when others do not.
Read More…average doses, and they experience side effects when others do not.
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antihistamineSide effects of antihistaminesUsed in sufficiently large doses, nearly all antihistamines produce undesirable side effects; the incidence and severity of the side effects depend both on the patient and on the properties of the specific drug. The most common side effect in adults is…
Read MoreUsed in sufficiently large doses, nearly all antihistamines produce undesirable side effects; the incidence and severity of the side effects depend both on the patient and on the properties of the specific drug. The most common side effect in adults is…
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antimicrobial agentSide effects and drug resistanceA number of antimicrobial compounds produce significant toxic effects in humans, but they are used because they have a favourable chemotherapeutic index; that is, the amount required for a therapeutic effect is below the amount that causes a toxic effect.…
Read MoreA number of antimicrobial compounds produce significant toxic effects in humans, but they are used because they have a favourable chemotherapeutic index; that is, the amount required for a therapeutic effect is below the amount that causes a toxic effect.…
Read More- therapeutic index
…produces unwanted and possibly dangerous side effects. This relationship is defined as the ratio LD50:ED50, where LD50 is the dose at which a drug kills 50 percent of a test group of animals and ED50 is the dose at which the desired effect is produced in 50 percent of a…
Read More…produces unwanted and possibly dangerous side effects. This relationship is defined as the ratio LD50:ED50, where LD50 is the dose at which a drug kills 50 percent of a test group of animals and ED50 is the dose at which the desired effect is produced in 50 percent of a…
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vaccineAdverse reactions…some risk of reaction, though adverse effects typically are very rare and very mild. The most common reactions to vaccines include redness and soreness around the vaccination site. More severe adverse reactions, such as vomiting, high fever, seizure, brain damage, or death, are possible for some vaccines. Such reactions are…
Read More…some risk of reaction, though adverse effects typically are very rare and very mild. The most common reactions to vaccines include redness and soreness around the vaccination site. More severe adverse reactions, such as vomiting, high fever, seizure, brain damage, or death, are possible for some vaccines. Such reactions are…
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