Clinical Snippets September 2021

Clinical Snippets – September 2021

Dr Dave Maplesden and Dr Jo Scott-Jones discuss “snippets” of clinical information relevant to New Zealand General Practice in this monthly conversation. This time, referring patients – the importance of using agreed processes for acute admissions and bowel screening, emaglifozin side effects, boron containing medications, hyperkalaemia, the choice of an ACEi or an ARB, and how not to prescribe Ivermectin for covid. 

1.  Waikato DHB – deferred acute referrals

A new directive is in place for what should happen when, after discussion with the registrar, it is deemed that the patient does not need to be seen acutely, but should have an outpatient appointment:

• If it is decided that the patient needs urgent follow up in clinic then the registrar is expected to organise this themselves.
• If it is considered that the patient may benefit from a semi-urgent or routine outpatient appointment then the GP/ Nurse Practitioner will be asked to refer. It cannot be guaranteed that the appointment will definitely occur as it will still have to go through the SMO triage process.

2. National Bowel Screening FOT Positive referrals

In BPAC search bar type FIT to display correct referral. It is not only important to refer participants through to the hospital but just as important to do the same referral if the participant wants to be seen PRIVATELY. NBSP is then able to update their information and close the loop knowing the participant has been followed up.  

3. Empagliflozin side effects

• Empagliflozin (Jardiance/Jardiamet) is used in the treatment of type 2 diabetes mellitus, to improve glycaemic control and reduce the risk of cardiovascular events in adults.
• Diabetic ketoacidosis and Fournier’s gangrene (necrotising fasciitis of the perineum) are rare, but serious and life-threatening conditions that can occur in patients on empagliflozin treatment.
• Inform patients about these potential adverse effects when initiating empagliflozin, including their signs and symptoms and when to seek medical attention.
• Patients taking empagliflozin should have a personalised ‘sick-day’ plan. See Health Navigator for information to include in such a plan and for excellent patient information leaflets on empagliflozin and empagliflozin/metformin.
• See the September 2021 Prescriber Update for more details

4.  Boron-containing medicines and fertility concerns in children

• The Medicines Adverse Reactions Committee (MARC) has recommended that a statement be added to medicine data sheets of boron-containing medicines, such as chloramphenicol eye drops, based on theoretical evidence that use may adversely affect future fertility. This advice specifically relates to use of boron-containing eye drops in children aged under two years.

• Chloramphenicol eye drops administered as one drop four times a day for the treatment of bacterial conjunctivitis is unlikely to exceed the threshold for boron in children aged under two years. Chloramphenicol ointment does not contain boron and therefore can be used as an alternative if caregivers are concerned.

5.  Reminder: hyperkalaemia caused by amiloride or spironolactone

Key Messages from theSeptember 2021 Prescriber Update

• Hyperkalaemia is a well-established risk of treatment with potassium-sparing diuretics such as spironolactone and amiloride.  The risk of hyperkalaemia is increased in patients with renal or hepatic impairment, the elderly, and those receiving concomitant medicines that can increase potassium.
• Examples of medicines that increase potassium include angiotensin-converting enzyme inhibitors (ACEis), angiotensin receptor blockers (ARBs) and non-steroidal anti-inflammatory drugs (NSAIDs)
• Regular monitoring of serum potassium is recommended especially when therapy is initiated, when dosages are changed or with any illness that may cause renal dysfunction
• Relevant preparations include frusemide/amiloride (Frumil), amiloride/hydrochlorothiazide (Moduretic) and spironolactone (Spiractin, Spirotone)
• An 2011 BPAC article on primary care management of electrolyte disturbances gives lots of practical advice including:  Urgent referral to secondary care is recommended for patients with serum potassium ≤ 2.5 mmol/L or ≥ 7 mmol/L, rapidly decreasing or increasing levels, neuromuscular symptoms or ECG changes, or if the patient is systemically unwell. 

6.  ACEi or ARB

• A recent Goodfellow Gem was headed ‘Time to switch from ACEis to ARBs – same efficacy but safer’ noting  ahead-to-head comparison trial of ARBs vs ACEis exhibited no difference in outcomes except for fewer drug withdrawals due to adverse effects with ARBs.

• In another study, ARBs had significantly lower risks of angioedema, cough, pancreatitis, and GI bleeding than patients on ACEis. The hazard ratio of angioedema associated with ACEis versus ARBs is over 3.  Although rare (incidence 0.1-0.7%), it remains an adverse event of concern as occasionally it can be fatal.

• In New Zealand, Pharmac fully funds Losartan and Candesartan, so there is no longer any funding barrier to ARB usage.

• A recent BPAC article on ACEi prescribing notes ACEi should be considered first line in patients with heart failure or following an MI while ARB can be considered equal first line with an ACEi for hypertension, CKD and diabetic nephropathy.

7.  Prescribing or authorising import of Ivermectin

(i)  The MCNZ statement ‘Good prescribing practice (2020)’ includes: 

• Be familiar with the indications, adverse effects, contraindications, major drug interactions, appropriate dosages, monitoring requirements, effectiveness and cost-effectiveness of the medicines that you prescribe.

• Prescribe in accordance with accepted practice and any relevant best practice guidelines. Prescribing outside of accepted norms should only occur in special circumstances with the patient’s informed consent.

• You may prescribe unapproved medicines or prescribe medicines for a purpose for which they have not been approved. However, if you decide to do so, you must take responsibility for overseeing the patient’s care, including monitoring and any follow-up treatment. You must make a clear, accurate and legible record of your reasons for prescribing any unapproved medicines and of the patient’s consent.

• Medicines or treatment must not be prescribed for your own convenience or simply because patients demand them.

(ii)  A recent Tools for Practice publication titled ‘Opening a can of helminths:Ivermectin for COVID-19’ poses the clinical question ‘Does ivermectin improve clinical outcomes in COVID-19?’.  The current evidence is reviewed with the conclusion:   The best available evidence does not show that ivermectin improves clinically important outcomes in COVID-19. Use in COVID-19 is discouraged.

(iii)  The RNZCGP has published a statement by College medical director Dr Bryan Betty that includes:  Ivermectin can, and does, cause harm when misused.  Prescribing it could well mean that even if the patient had given consent, the doctor could still be held liable for making an ill-informed decision on a medication that at this point has not been shown to provide benefit and could cause harm. It would be difficult to justify this position with either the Medical Council or the Health and Disability Commissioner.

(iv)  Medsafe has recently published a Prescriber Alert that includes:

• Medsafe and the Ministry of Health strongly recommends that ivermectin is not used for prevention or treatment of COVID-19. Ivermectin is NOT APPROVED to prevent or treat COVID-19, which means that Medsafe has not assessed the safety and efficacy for this use. Inappropriate use of ivermectin can be dangerous.

• Ivermectin is not approved in New Zealand (or in other OECD countries) to prevent or treat COVID-19 disease in humans.  When ingested in high doses, ivermectin can have a serious effect on humans, with symptoms including low blood pressure, worsening asthma, severe autoimmune disorders, seizures and liver damage.

• Regarding a prescriber’s authorisation of Ivermectin imports:  The authorised prescriber must be satisfied that the individual’s clinical need for the medicine outweighs the risks of taking the imported medicine. By authorising release, the authorised prescriber takes responsibility for prescribing the medicine for that individual.

• Medsafe has not evaluated the safety, quality and effectiveness of medicines imported by patients. These medicines may be of poor quality, sub or super potent, contaminated, adulterated or counterfeit. Taking these medicines can put people at serious risk of unpredictable or severe side effects.