transdermal patches

see also:

• pharmacology main index
• nitrates including GTN
• opiates and opioids

• transdermal patches can be an effective drug delivery route
• they deliver medication at a constant rate via the skin into the bloodstream for a prolonged effect.
• increasing numbers of medications are becoming available in transdermal patch form.
• however they may also be associated with serious adverse events.
  • Australian and international reports show high incident rates particularly with opioid (fentanyl, buprenorphine resulting in opioid respiratory depression) and glyceryl trinitrate patches (resulting in postural hypotension).
• appropriate prescribing, correct application and removal, careful education and monitoring of patients and correct disposal can reduce the risk of adverse events.

• prescriptions on drug charts should include:
  • drug generic name +/- trade name
  • patch dose
    • hourly dose for fentanyl
    • % concentration for lignocaine
    • most other patches: 24 hour dose
  • frequency of application
    • fentanyl is usually every 3 days
    • buprenorphine is applied every week
    • for patches > 24hrs, prescriber MUST write the nursing ‘Check Application’ section
  • drug-free periods
    • if the patch has specific ON and OFF times (e.g. glyceryl trinitrate patches), clearly specify this on the “Administration times” section of the medication chart.
      • eg. if use patch overnight only, indicate OFF 0800 and ON 2000
  • timing of application
    • a midday changeover for opioid patches is preferred as this allows decisions to be made on the morning round prior to any re-application.

• BEFORE applying new patch:
  • check to ensure old patch has been removed
    • discard patch into the sharps container/infectious waste bin by folding adhesive sides together.
    • discarding of opioid patches is to be witnessed by two RN/RM/ENmed/MO one of whom must be an RN or RM.
      • an entry is to be made in the comments section of the Controlled Drug (CD) administration book, including the method of destruction.
  • do not cut a patch to adjust a dose
• application:
  • avoid exposure to the drug by wearing protective gloves during application, removal and disposal. Without touching the adhesive, remove the plastic backing.
  • apply the patch evenly to clean, dry, hairless skin on the upper body, ideally a site that is easily accessed by staff to check application.
  • rotate the site with each application to minimise risk of skin reactions.
  • document application on the:
    • medication chart (document the time and date).
    • Functional Maintenance Care Plan
    • patch itself (document the time AND date of application).
  • note whether the patch requires a drug-free period e.g. glyceryl trinitrate and some nicotine patches.
  • communicate patch information on handover.
  • for patches that remain in situ for more than 24 hours (Figure 3), to prevent inadvertent removal of patch or doubling up of patches, every patch must be checked once a shift: AM (Morning Shift), PM (Afternoon Shift) and Night (Night Shift).
    • this is to be documented by:
      • if the patch is correctly in place tick the appropriate box of the ‘Check Application’ section located in the administration section of the order.
      • if patch falls off (either partly or entirely), write ‘OFF’ in the ‘Check Application’ section. Do not re-apply the same patch. Inform the treating team or pharmacist and apply a new patch if deemed appropriate and ensure that the prescription is altered on the drug chart if necessary.
• other considerations:
  • Fentanyl patch dosing may require the application of more than one patch eg 37 microg/hour requires two patches (25 microg/hour and 12 microg/hour patch).
  • do not apply patches to broken, infected or cut skin. If patient has body hair where a patch is to be applied, the hair must be cut short and not shaved.
  • do not apply the patch immediately after a hot shower. Wait until the skin is cool and dry.
  • do not apply heat (including heat pack, electric blanket, hot water bottle, sauna, and spa) on or near the patch, as it may result in an increased rate of drug absorption.