Ibuprofen Aluminium hydroxide

Information is very limited but it would appear that if rapid analgesia is needed with either mefenamic acid or tolfenamic acid, magnesium hydroxide can be given concurrently but aluminium hydroxide should be avoided. However, note that this applies to the fasted state, whereas NSAIDs are usually taken with or after food. Also note that magnesium hydroxide increased the endoscopically-detected gastric toxicity of ibuprofen in one study, see NSAIDs Ibuprofen and related drugs -i- Antacids , below. Aluminium hydroxide markedly reduces the speed of absorption. Sodium bicarbonate does not interact. Consider also NSAIDs Miscellaneous + Antacids , p.l42. 

Ibuprofen - a bulk active pharmaceutical. An example is the synthesis of 4-isobutylacetophenone, a key intermediate for the highly successful analgesic ibuprofen (19). The conventional method is a Friedel-Craft alkylation catalysed by aluminium trichloride (Scheme 2.6). To produce 5000 tonnes of 4-isobutylacetophenone some 3800 tonnes of aluminium trichloride are used. The spent catalyst has to be disposed of as aluminium hydroxide. In addition large amounts of acidic gaseous emissions (HCl) have to be scrubbed from the off-gas stream. 

NSAIDs ANTACIDS 1. Magnesium hydroxide T absorption of ibuprofen, flurbiprofen, mefenamic acid and tolfenamic acid 2. Aluminium-containing antacids l absorption of these NSAIDs Uncertain These effects are 1 by taking these drugs with food... 

A small reduction in ketoprofen absorption occurred with aluminium-magnesium hydroxide, but dexketoprofen, ibuprofen and flurbiprofen were not affected, and naproxen showed a slight increase in rate and extent of absorption. Aluminium phosphate had no effect on ketoprofen absorption. 

Magnesium hydroxide appears to improve the rate of absorption of some acidic NSAIDs (which become more soluble as the pH rises) such as ibuprofen and flurbiprofen. Why this increased the gastric toxicity of ibuprofen in the one pharmacodynamic study is unclear. Sodium bicarbonate appears to have a similar effect on rate of absorption. Aluminium antacids do not produce soluble salts with these NSAIDs, and may therefore reduce the rate/extent of absorption. 

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