Intramuscular injection advantages/disadvantages

Alternative options are increasingly favoured in the form of oral iron polymaltose complexes. These are more expensive but attractive in that complications are less frequently encountered and the lethal toxicity that follows release of large amounts or ionic iron into the circulation does not occur. Carbonyl iron is not often used but available in some countries. In contrast combinations with vitamins and cobalt, still popular in certain areas, have no documented advantage and add quite unnecessary cost. Other routes are intramuscular injections and, except where oral administration is precluded, have disadvantages in that mobilization is unpredictable. Conversely, it is feasible to replace iron as a single total dose infusion but such procedures need to be given under supervised conditions. It is reiterated that the rate of rise in haemoglobin that follows adequate oral replacement is comparable to that achieved par-enterally. 

Advantages of the intramuscular and subcutaneous routes include an increased reliability and precision in the drug blood level Anally achieved and reasonably rapid absorption and onset of drug action. There are, however, serious disadvantages as well. Pain, tenderness, local tissue necrosis (primarily with highly alkaline injections), microbial contamination, and nerve damage may be associated with these forms of parenteral administration. 

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