Drug application intravenous

Ajmaline (intravenously only) and its orally applicable propyl-substituted prodrug prajmaline are classified as class IA drugs, but due to their long dissociation time constant can also be considered as class IC compounds. 

The drug is metabolized rapidly in the liver, kidney, intestinal mucosa, and even red blood cells. Therefore it has a plasma half-life of only 10 min after bolus intravenous application. The major metabolite, uracil arabinoside (ara-U), can be detected in the blood shortly after cytarabine administration. About 80% of the dose is excreted in the urine within 24 h, with less than 10% appearing as cytarabine the remainder is ara-U. After continuous infusion, cytarabine levels in the liquor (cerebro-spinal fluid) approach 40% of that in plasma. Continuous infusion schedules allow maximal efficiency, with uptake peaks of 5-7 pM. It can be administered intrathecally as an alternative to methotrexate. 

Obviously, if you wish to treat a skin condition or infection, a preparation that can be applied topically would be the preferred option. Similarly, inhalation would be the first choice if trying to treat a pulmonary or bronchial condition, such as asthma. Dermal application would also be the first choice for localized tissue treatments (e.g. muscle injury), provided that the drug can be absorbed through the skin. However, in most other situations it is necessary for drugs to enter the bloodstream in order for them to be transported to their site of action. This is most commonly achieved by ingestion, or by intravenous (i.v.), intramuscular (i.m.) or subcutaneous (s.c.) injection when the oral route is not suitable. 

Aprotinin. Aprotinin is a naturally occurring serine protease inhibitor, has found widespread applications either by the intravenous route or as a component of biological sealants, because of its ability to decrease blood loss, and, as a consequence, transfusion requirements. Anaphylactic reactions are mediated by IgG and IgE antibodies. The risk of anaphylactic reactions has been estimated between 0.5 and 5.8% when used intravenously during cardiac surgery, and at 5 for 100,000 applications when used as a biologic sealant [25]. Patients previously treated with this drug present an increased risk and any new administration should be avoided for at least 6 months following an initial exposure [25]. 

Drugs are administered by various means from oral to intravenous to topical. The oral route is a relatively slow process where a drug must be absorbed across the GI tract and then passed through the liver and metabolized before it becomes available to bind to receptors and perform its intended function. On the other hand, intravenous application is quick but has the potential of fast systemic reaction if adverse reactions occur. In the case of topical administration, the effects of the drug are localized. 

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