For someone on HIV treatment (taking HAART), there may be times when it is necessary to switch from one drug regimen to another. In some cases, the need for this might be due to the drug used no longer being effective (virological failure), leading to a rise in the viral load. Such drug resistance may be due to a number of factors, but often is due to poor adherence. More often, though, drugs are switched because of side effects.
A recent study of treatment switching in the UK shows good news, though. The number of people switching is dramatically lower now (2011) than it was even 5 years ago (2006). This shows that today’s drug regimens are much easier to tolerate than the older regimens.
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