Ulceration, gastrointestinal

NS AIDs Cyclooxygenases (COX-1, COX-2) l Prostaglandins l Thromboxanes l Sensitization of sensory neurons f Inhibition of spinal neurons Nonselective gastrointestinal ulcers, perforation, bleeding, renal impairment COX-2 thrombosis, myocardial infarction, stroke... 

Celecoxib, which has a low selectivity for COX-2 compared to COX-1, is still available, although its more selective successor, valdecoxib has been withdrawn. Etoricoxib, the successor to rofecoxib, is marketed in Europe but not in the USA. In a large multinational clinical trial, etoricoxib caused no more thromboembolic events than diclofenac, but after 18 months the incidence of gastrointestinal ulcers and bleeding was the same for both drugs [4]. 

The answer is a. (Hardman, pp 1247-1251.) 5-Huorouracil is a pyrimidine antagonist that has a low neurotoxicity when compared with other fluorinatecl derivatives however, its major toxicities are myelosup-pression and oral or gastrointestinal ulceration. Leukopenia is the most frequent clinical manifestation of the myelosuppression... 

In all tested organisms, PCBs — especially PCBs with 2,3,7,8-TCDD-like activity — adversely affected patterns of survival, reproduction, growth, metabolism, and accumulation. Common manifestations of PCB exposure in animals include hepatotoxicity (hepatomegaly, necrosis), immunotox-icity (atrophy of lymphoid tissues, suppressed antibody responses), neurotoxicity (impaired behavior and development, catecholamine alterations), increased abortion, low birth weight, embryolethality, teratogenicity, gastrointestinal ulceration and necrosis, bronchitis, dermal toxicity (chloracne, edema,... 

The FDA approved this selective cyclooxigenase (COX)-2 inhibitor (Vioxx) for the treatment of pain and inflammation in 1999. This NSAID demonstrated to have a lower risk of side effects such as gastrointestinal ulcers and bleeding than nonse-lective COX inhibitors, for example, ibuprofen. In 2004, a long-term study of Vioxx in patients at increased risk of colon polyps was halted because of an increased cardiovascular risk (heart attack, stroke) in the rofecoxib group. Subsequently, Merck withdrew the drug from the world market at the end of September 2004 [46]. 

Q19 Wh ich of the following products is NOT indicated as an agent to be used in gastrointestinal ulcer healing ... 

Arthrotec tablets contain the non-steroidal anti-inflammatory drug diclofenac and the prostaglandin misoprostol. The combination of the two active ingredients makes Arthrotec suitable in patients predisposed to gastrointestinal ulceration. Dulco-lax (bisacodyl) tablets act as a stimulant laxative. Voltarol Retard tablets contain the non-steroidal anti-inflammatory drug diclofenac. All... 

Oral anticoagulants are ordinarily contraindicated in the presence of active or past gastrointestinal ulceration thrombocytopenia hepatic or renal disease malignant hypertension recent brain, eye, or spinal cord surgery bacterial endocarditis chronic alcoholism and pregnancy. These agents also should not be prescribed for individuals with physically hazardous occupations. 

All cholinesterase inhibitors should be used with caution in patients with cardiac conduction problems because vagotonic effects can lead to bradycardia. In addition, caution is warranted in patients with comorbid asthma, chronic obstructive pulmonary disease, bladder outlet obstruction, or seizures, as well as in patients at risk for gastrointestinal ulcers or bleeding (Fuller and Sajatovic 2000). 

It is an aminoglycoside antibiotic used only as luminal amoebicide and has no effect against extra intestinal amoebic infections. It is less toxic than other agents, but it should be used cautiously in patients with significant renal disease and with gastrointestinal ulcer. 

A major iimitation to the use of NSAIDs is gastrointestinal ulceration and bleeding, particularly in the stomach, due to suppression of protective gastric prostaglandins (PGs). NSAID-induced ulceration. The concomitant administration of the PGEl analogue, misoprostol, is more effective but is expensive and associated with an appreciable incidence of side effects, notably diarrhoea Renal adverse effects... 

Gastrointestinal ulceration may occur less frequently than with some other NSAIDs. A preparation combining diclofenac and misoprostol decreases upper gastrointestinal ulceration but may result in diarrhea. Another combination of diclofenac and omeprazole was also effective with respect to the prevention of recurrent bleeding, but renal adverse effects were common in high-risk patients. Diclofenac, 150 mg/d, appears to impair renal blood flow and glomerular filtration rate. Elevation of serum aminotransferases occurs more commonly with this drug than with other NSAIDs. 

Cat s claw has long been used in South America as an anti-inflammatory, antirheumatic, and contraceptive agent. It is also traditionally used to treat gastrointestinal ulcers, tumors, gonorrhea, dysentery, various skin problems, cancers of the female genitourinary tract, and intestinal disorders. Native South Americans use cat s claw to cleanse the kidneys and treat bone pain. Some Europeans report that it is useful in the treatment of AIDS when used in combination with zidovudine (AZT). The purported usefulness of cat s claw tea in the treatment of diverticulitis, hemorrhoids, peptic ulcer disease, colitis, parasites, and leaky bowel syndrome have fueled demand for the bark in the U.S. 

Comfrey (Symphytum officionale). Ointments made from comfrey are used topically for wound and bone healing. Comfrey tea and pills have been prescribed by herbalists to treat gastrointestinal ulcers and diarrhea. However, the FDA advised dietary supplement manufacturers to take comfrey off the market in 2001 because of the gathering evidence that comfrey taken internally causes severe liver toxicity. The FDA also noted the lack of evidence for comfrey s effectiveness. Comfrey should not be used by pregnant women or breastfeeding mothers. 

Adverse effects in patients include anorexia, nausea, vomiting, gastrointestinal ulceration, skin eruptions, bone marrow depression, reversible cholestatic jaundice, hepatic necrosis, dermatitis, and drug fever.2 LD50 (i.p., mouse) 157 mg/kg (i.p., hamster) 364 mg/kg.1... 

Only a few of the numerous animal studies found any effects. Gastrointestinal ulcerations were reported in minks after an acute oral exposure to a lethal dose of 2,3,7,8-TCDD (Hochstein et al. 1988), and... 

Non-steroidal antiinflammatory drugs (NSAIDs) are the main therapeutic agents for the treatment of the symptoms of arthritis. The drugs seem to inhibit the enzyme cyclooxygenase and consequently the conversion of arachidoic acid into prostaglandins. The main drawbacks of NSAIDs are severe side effects, including gastrointestinal ulceration and... 

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