Which route of administration does SL indicate?

The abbreviation "SL" stands for sublingual, which refers to a specific route of administration where a medication is placed under the tongue. This method allows the drug to dissolve and be absorbed directly into the bloodstream through the tissues beneath the tongue, leading to rapid onset of action. This is particularly useful for medications that need to act quickly or are poorly absorbed through the gastrointestinal tract.

Medications administered sublingually can bypass first-pass metabolism in the liver, which can enhance their bioavailability. This is a significant advantage compared to other routes of administration, as it can lead to faster therapeutic effects.

Other options describe different routes. Intravenous is the administration directly into the bloodstream, transdermal involves absorption through the skin, and intramuscular refers to injection into muscle tissue. Each of these routes has its own indications, advantages, and specific uses in clinical practice, but none match the definition that "SL" represents.