Injectables PDF

Injectables Some defini2ons - Injec2on. o A volume of 50 mL or less, delivered directly from a syringe and needle, over a short period of 4me. Can be into a vein, muscle, artery, under the skin(subcutaneous), or into the skin/fat layer. - Bolus injec2on....

Injectables Some defini2ons - Injec2on. o A volume of 50 mL or less, delivered directly from a syringe and needle, over a short period of 4me. Can be into a vein, muscle, artery, under the skin(subcutaneous), or into the skin/fat layer. - Bolus injec2on. o (Also called intravenous push) When rapid administra4on of a medica4on is needed, such as in an emergency; when drugs cannot be diluted; and when the therapeu4c purpose is to achieve a peak drug level in the bloodstream of the pa4ent. - Infusion o Infusion. Delivered directly into the blood stream. Delivery over a longer period (>15 min) using a PICC line, via an IV bag, or using a porta cath. o For large volume o Some4mes, the dose is not the key, maintaining certain concentra4on of drug in bloodstream can be a key. o Injec4on and infusion à not interchangeable - - Mul2-dose vial o Vial of API solu2on that contains more than one dose of medica2on. They typically contain an an4microbial preserva4ve to help prevent the growth of bacteria, but the preserva4ve has no effect on viruses and does not protect against contamina4on when healthcare personnel fail to follow safe injec4on prac4ces. - Y-site (Y-set) o A three-way connector that allows the administra4on of two different solu4ons at the same 4me. Can be infusion + infusion or infusion + injec4on. o Used when pa4ent have comorbidi4es à need more than one injec4on or drug. Types of IV fluids - Glucose. (Dextrose), 5% w/v, isotonic (308 mOsM, FPD = -0.52 oC). - Ringer’s. NaCl, KCl, CaCl2, NaCO3H. Source of bicarbonate for mild-to-moderate metabolic acidosis. - Ringer’s lactate/Hartmann’s. pH 5-7, NaCl, Na-lactate, KCl, CaCl2. Source of bicarbonate for mild-to- moderate metabolic acidosis. - Plasma-lyte148. pH 7.4, NaCl, Na-gluconate, Na-acetate, KCl, MgCl2. Used to provide hydra4on and electrolytes. - Sodium chloride. 0.9% w/v, isotonic (308 mOsM, FPD = -0.52oC). - NaCl + glucose. NaCl (0.18% w/v) and glucose (4% w/v). Example of the importance of excipient selec2on - Massive difference in doses à important. - Remember what’s safe and what’s toxic. - When you make carbopla4n in NaCl, it became cispla4n but very overdosed (danger). Colloid solu2ons - Certain electrolytes, but also: o Human albumin o Starch o Dextran, or o Gela4n - Used as plasma expander in the treatment of shock. Colloidal par4cles do not penetrate capillary walls, so stay in the blood stream and maintain vascular volume. Types of injec2ons - Epidural o Mainly for delivering anaesthe4cs. Involve syringe injec4on or catheterisa4on (to allow further dosing) of the API into the epidural space next to the spinal cord. o Opioids - Intramuscular (IM) o Used to deliver drugs deep into the muscles. Typically, in areas away from veins and arteries (thigh, shoulder, buaocks). Examples include the delivery of vaccines, Botox,, and testosterone. - IM-suspension-based formula2ons o Useful when you want sustained release (API must dissolve). o You can have solid in the injec4on. (oil based) à IV you never have solid in injec4on. - EpiPen o IM injec4on o Epinephrine (adrenaline) o Used for anaphylaxis. o Untrained personal. o Blue to the sky, orange to the thigh. o Hold in place 3 sec. - Subcutaneous and intradermal administra2on o Small volume. Typically used for insulin and cosmeceu4cals. - Intra-arterial (cardiac, arterial line). o Drug delivery directly into an artery. Harder to do (more risk), as arteries don’t tend to to be near the surface. Not usually used for drug delivery. Requires the use of catheter and painful (anaesthe4c needed). - Less common injec2ons: Do not memorise o Intra-cameral à An injec4on into the anterior chamber of the eye (e.g. lignocaine, cataract surgery). o Intra-vitreal à An injec4on into the vitreous fluid at the back of the eye (e.g. Avas4n, macular edema). o Intra-osseous. à An injec4on into the bone marrow (e.g. any drug delivered via IV, for IV compromised pa4ents; non-collapsible point of entry). o Intra-athecal. à An injec4on into cerebrospinal fluid (e.g. baclofen; muscle relaxing). o Intra-ar2cular. à An injec4on in a joint space (e.g. cor4costeroids, osteoarthri4s). Microneedles - Defini2on o Micron-sized needles aaached to a syringe or other medical device (roller, patch, pen) are widely used for delivery of therapeu4c agents and diagnos4c applica4ons. - Benefits o Self-applica4on, less painful, don’t need to include an API. - Different types o Microinjec4on microneedles o Non -injec4on microneedles o Patches o Dissolving patches o Coated microneedle patches o Bare microneedle patches o Radiofrequency microneedles o Microneedle rollers Benefits of injectables - Systemic or localised drug delivery. - Rapid ac4on - No absorp4on issues. - Accurate dosing - Reduce first pass metabolism. Disadvantages and considera2ons of injectables - Pain/swelling/discomfort of pa4ent - Needle s4ck injuries. - Much of the 4me has to be done by trained medical staff. - Solu4on (no solids) for direct to blood stream. - Isotonic for IV. - Sterile. Things can that go wrong with IV administra2on. - Bacterial or viral infec2on. o Problem for obvious reasons = systemic infec4on very quickly. - Air embolism. (Also called gas embolism) o Occurs when one or more air bubbles enter a vein or artery and blocks it. - Extravasa2on. o Uninten4onal administra4on or leakage of solu4on into the surrounding 4ssue. (Pain, irrita4on, redness, necrosis). - Phlebi2s. o Means an inflamma4on of the vein. Damage to the blood vessel walls or impaired flow. Due to pH or osmolarity of solu4on. (Same as before + swelling) - Thrombophlebi2s. o One or more blood clots (usually in the legs). Non-drug example: DVT when flying. AstraZeneca COVID-19 vaccine: cerebral venous sinus thromboses (CVST) Infusion rate calcula2ons