Different routes of administration
- Mouth
- Nose, eye, ear
- Lungs
- Rectal
- Vaginal
- Parenteral – I/V, S/C, I/M, Intra spinal, intra cardiac
- Topical
Tablets
- S/L = Sublingual (under the tongue). Medicine can get into the systemic circulation quicker and it doesn’t go into the stomach so therefore it isn’t digested
- Buccal = lip, gum and cheek, dissolved slowly so it has a prolonged release effect
- Orodispersible = tablets dissolve directly in the mouth
- FC = film coated
- SC = sugar coated
- Gastro-resistant = there is a coating which is designed to hold the tablet together in acid conditions i.e. the stomach and therefore release the drug in the intestines.
- EC = enteric coated, prevents it from being dissolved in the stomach
- Dispersible = dissolve or disperse in water
- Effervescent = designed to break down quickly and release carbon dioxide when dropped in liquid, tends to go fizzy
When can effervescent tablets not be used in patients?
When the patient has high blood pressure
What can you not take at the same as an EC tablet and why?
Antacids because it makes it dissolve in the stomach (alkaline pH) when it should dissolve in acidic pH
How do effervescent tablets work?
- These tablets are made by compressing the component ingredients into a dense mass.
- They deliver drugs to the body rapidly, because the drug is delivered in the form of a solution that is easy to absorb.
- Dosage control also is easier, and effervescent tablets can be used to protect certain ingredients from the highly acidic environment of the stomach, so that the body has a chance to access them.
- Large doses of medication can be easily delivered by effervescent tablets, because the patient just needs to drink one glass of fluid
Capsules
- Capsules can be filled with liquid, powder or spansules (different coloured beads)
- Some not oral
- Only open a capsule when it is indicated to do so (may state in the BNF)
Who might not want to take a capsule?
- Vegetarians may not want to take a capsule as it may contain gelatin
- Outside of a capsule gets sticky quickly so certain drugs cannot be put into a capsule
Modified release
- Capsules and tablets
- MR, SR, Retard = 12 hour release
- XL, Prolonged release = 24 hours release
If a prescription for a modified release product is generic is it a problem?
Generic can have a different preparation to branded preparations (eg lithium)
Oral Liquids
• Mixtures, solutions, linctuses, syrups, elixir, emulsions, suspensions
• Temperature, sunlight and discard date can affect their storage
- Suspensions need to be shaken before administration (Eg kaolin and morphine)
Nose, Ear, eye
- Drops and Spray
- Metered dose sprays
- Nose preparations for local and systemic use
- Eye preparations are normally for local use
What tonicity and pH should eye and nose drops ideally be?
Tonicity should be Isotonic
pH should be 5 or 6 for nose and 7 for eyes
Should a baby have a nasal spray?
No use nasal drops instead as you can’t determine the dosage you put into a baby’s nose using a nasal spray
Name a nose formulation for systemic use?
Calcitonin spray, Beconase aqueous nasal spray (beclometasone)
After using eyedrops, press your finger against the inside corner.. why?
Pressing inside corner of your eye prevents it from entering into the lacrimal canal which connects to you nose
Suppositories and pessaries
Suppositories can be systemic or local
- Suppositories melt at around body temperature
(eg. glycerin will lubricate and irritate so are used for constipation)
Gelatine bases are kept in water
Creams and Ointments
Ointments are more oil based
Use finger tip unit for steroids
