Pharmacology 3Safety and Effectiveness in Medicines Administration

Applying the Evidence Base

Recap from Pharmacology 1 and 2

Pharmacokinetics what the body does to the drug

Pharmacodynamics what the drug does to the body

Desired effects?Adverse effects?

Evaluating effects-ongoing monitoring

Pharmacokinetics

What are the key considerations with patients?

• Ability of the liver to metabolise drugs

• Ability of the liver to excrete drugs

Pharmacodynamicss

Drug Effects on the body

They can be used to • Depress activity • Stimulate activity• Destroying cells

(cytotoxicity) • Irritate – produce

adverse effects• Replace

substances • Diagnose

• Key considerations:

• Desired activity • Undesirable effects • Therapeutic window

Therapeutic Window

Blood level of the drug

Response

Recap Case 1Co-codamol (BAN) is a non-proprietary name used to

denote a compound analgesic, a combination of codeine phosphate and paracetamol

Co-codamol tablets are used for the relief of mild/moderate (or in the case of 30/500mg - severe) pain.

Side effects can include of this drug can include: constipation, skin rashes, dizziness, sedation, shortness of breath, hypersensitivity reaction, fainting (syncope or near syncope), nausea and/or vomiting, confusion, loss of short-term memory, drowsiness, changes in blood, allergic reactions, euphoria, dysphoria, abdominal pain, pruritus (itching), easy bruising and bleeding gums (BNF 55)

Use the BNF• Check the side effects- Co-Codamol

• Go to http://www.bnf.org/bnf/index.htm

• Create a login

BNF work• Check the side effects- Co-Codamol

Side effects of this drug can include: Constipation, Skin rashes, Dizziness, Sedation, fainting (syncope or near syncope), euphoria, dysphoria, confusion, loss of short-term memory, drowsiness, Shortness of breath, Hypersensitivity reaction, Nausea and/or vomiting,Blood dyscrasias (thrombocytopenia and agranulocytosis) , Allergic reactions,Abdominal pain,Pruritis (itching),Easy bruising and bleeding gums (BNF 61)

Compare EMC http://www.medicines.org.uk/EMC/

Undesirable effects: Codeine can produce typical opioid effects including constipation, nausea, vomiting, dizziness, light-headedness, confusion, drowsiness and urinary retention. The frequency and severity are determined by dosage, duration of treatment and individual sensitivity. Tolerance and dependence can occur, especially with prolonged high dosage of codeine.

• Adverse effects of paracetamol are rare but hypersensitivity including skin rash may occur. There have been reports of blood dyscrasias including thrombocytopenia and agranulocytosis, but these were not necessarily causally related to paracetamol.

• Regular prolonged use of codeine/DHC is known to lead to addiction and tolerance. Symptoms of restlessness and irritability may result when treatment is then stopped.

• Prolonged use of a painkiller for headaches can make them worse. Very rare occurrence of pancreatitis.

Reviewing Case Example 1

Mrs Powell (age 45years) was prescribed

Co-codamol 15-500 (whilst in hospital) to treat her arthritic pain.

She had been taking this medication for one month and her pain relief did improve.

Her side effects were:• Feeling drowsy and felt a little nauseated in

the first 3 weeks of taking these. WHY and WHEN WOULD THIS RESOLVE WHY

• Constipated WHY HOW could this be MANAGED.

She was considering a change in Pain relief

• PARACETEMOL

• IBUPROFEN

BNF – Look up Ibuprofen

• http://www.medicines.org.uk/EMC/medicine/10849/SPC/Brufen+400+mg+Tablets/

Some Clinical Practice Considerations

She asked:

Can I take my other tablets (OTC medication) with the medicine I have been prescribed? (mentioning. Ibuprofen, mixes of Aspirin and Paracetamol (‘Anadin Extra’) and paracetamol alone )What can be mixed?

Does it matter if I take the tablets at varying time intervals?

The nurse must be able to give the patient accurate information, to ‘empower’ the patient to be able to safely self medicate (NMC 2008).

‘Errors’

The nurse with knowledge and understanding of pharmacology will be more confident in drug administration

Who is responsible for ‘correct dose administration ’ with respect to medication?

What professional principles are relevant?

What ethical principles can be applied to the issue of patients getting the right dose?

‘Errors’

The nurse with knowledge and understanding of pharmacology will be more confident in drug administration

Who is responsible for ‘health education’ with respect to medication?

What professional principles are relevant?

What ethical principles can be applied to the issue of patients understanding side effects?

Development of Knowledge and Skill with Medicine Administration

Knowledge and understanding of pharmacology will generate more confidence in drug administration

Nurses are responsible for ‘correct dose administration ’.