Drug injection taking drugs, injection is favoured by some people as the full effects of the drug are experienced very quickly, typically in five to ten seconds. It also bypasses first-pass metabolism in the liver, resulting in higher bioavailability and efficiency for many drugs (such as morphine or diacetylmorphine/heroin; roughly two-thirds of which is destroyed in the liver when consumed orally) than oral ingestion would. The effect is that the person gets a stronger (yet shorter-acting) effect from the same amount of the drug. Drug injection is therefore often related to substance dependence. In a recreational context, the shorter, more intense "high"
Drug nomenclature are called either trimethoprim/sulfamethoxazole or co-trimoxazole. Similarly, co-codamol is codeine-acetaminophen, and co-triamterzide is triamterene-hydrochlorothiazide. The USP ceased maintaining PENs, but the similar "co"-prefixed BANs are still current. For drugs that make it all the way through development, testing, and regulatory acceptance, the pharmaceutical company then gives the drug a trade name, which is a standard term in the pharmaceutical industry for a brand name or trademark name. For example, Lipitor is Pfizer's trade name for atorvastatin, a cholesterol-lowering medication. Also, Atocor is an Atorvastatin brand in India. Drug names are often subject to legal regulation, including approval for new drugs