Pentoxifylline adverse effects

PENTOXIFYLLINE ANTIBIOTICS Ciprofloxacin may t pentoxifylline levels Uncertain likely to be due to inhibition of hepatic metabolism Warn patients of the possibility of adverse effects of pentoxifylline... 

In 52 adults with cerebral malaria who were randomized to either quinine dihydrochloride alone (n = 32) or a combination of quinine and pentoxifylhne (n = 20), the addition of pentoxifyUine significantly improved coma resolution time from 64 to 22 hours and reduced mortality from 25% to 10% (1). Three days after therapy, serum tumor necrosis factor alfa concentrations fell significantly in those who received pentoxifylline. Pentoxifylline caused no serious adverse effects that necessitated withdrawal. 

Information on this interaction and its clinical relevance is limited. The author of the pharmacokinetic study suggests that, if the drugs need to be used together, the dosage of pentoxifylline should be halved. In the absence of other information, if a short-course of ciprofloxacin is required in a patient taking pentoxifylline, this may be a sensible precaution. Alternatively, because the increase in AUC was minor, it may be sufficient to recommend a reduction in pentoxifylline dose only in those who experience adverse effects (e.g. nausea, headache). Note that ciprofloxacin has been used to boost pentoxifylline levels in studies investigating the possible therapeutic value of pentoxifylline s ability to inhibit various cytokines. For example, ciprofloxacin 500 mg twice daily was used with pentoxifylline 800 mg three times daily for up to one year in patients with myelod-ysplastic syndrome. ... 

Cimetidine increases plasma pentoxifylline levels to a moderate extent, which may increase the incidence of adverse effects. 

A study in 10 healthy subjects found that the mean steady-state plasma levels of controlled-release pentoxifylline 400 mg every 8 hours were raised by about 27% when cimetidine 300 mg four times daily for 7 days was added. Adverse effects such as headache, nausea, and vomiting were said to be more common and bothersome while taking the cimetidine. ... 

The findings of this study suggest that this interaction may be clinically relevant. If cimetidine is required in a patient taking pentoxifylline, monitor for adverse effects, and decrease the pentoxifylline dose if problems... 

Evidence from one study su ests that ciprofloxacin increases the serum levels of pentoxifylline, and may increase the incidence of adverse effects. In some clinical studies ciprofloxacin has been used to boost the levels of pentoxifylline. 

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