Products
Injection preparations are approved as medicinal products.
Structure and properties
Injection preparations are sterile solutions, emulsions, or suspensions prepared by dissolving, emulsifying, or suspending the active ingredient and excipients in water or a suitable nonaqueous liquid (e.g., fatty oils). Compared with infusions, these are usually small volumes in the range of less than a milliliter to a few milliliters. They can also be freshly prepared from a powder or concentrate prior to administration. Requirements for injection preparations:
- Sterile
- Pyrogen-free
- Blood isotonic / isohydric
- Free from suspended solids
Isotonicity is less relevant for small volumes than for infusions.
Effects
Because of the direct application, the dose enters the bloodstream rapidly. Therefore, the pharmacologic effects occur much more rapidly than with peroral administration. This is particularly important for medical emergencies. Injections can also be administered to unconscious patients. In this regard, it should be noted that injectables with a depot effect also exist. Another reason for injections is insufficient oral bioavailability, for example of biologics. Finally, some drug targeting can also be achieved with injections.
Indications
For numerous indications.
Dosage
Injections are administered parenterally. Typical routes of administration include intravenous injection (into a vein), subcutaneous injection (under the skin), and intramuscular injection (into a muscle). Injections are usually administered by healthcare professionals. However, there are also drugs on the market that may be injected by patients themselves after adequate instruction. These include, for example, biologics, insulins, antidiabetics, low-molecular-weight heparins and antirheumatic drugs. Before administration, it must be checked that the preparation meets the requirements. Suspensions must be agitated or shaken back and forth. The injection site must be disinfected before and after injection. Place used syringes in a disposal box. Syringes used include disposable syringes and needles, pens, prefilled syringes, and auto-injectors.
Adverse effects
The most common possible adverse effects include local reactions at the injection site, such as pain, a feeling of tightness, redness, rashes, discomfort, and bleeding. Fear of injections: An injection may cause some patients to experience unpleasant symptoms such as pallor, sweating, lightheadedness, dizziness, and fainting. This is caused by a drop in blood pressure due to an autonomic response from a low heart rate and vasodilatation. Injuries: In case of improper handling and accidents, the needles can cause injuries. Accidental needle sticks with used syringes can transmit infectious diseases such as hepatitis B or HIV. Allergic reactions: Very rarely, a severe allergic reaction, called anaphylaxis, may develop after an injection in sensitive patients. Other side effects depend on the active ingredients used.