This issue of New Zealand’s Prescriber Update provides critical safety information and regulatory updates for healthcare professionals. The key articles are summarized below.
1. Systemic Fluoroquinolone Antibiotics: Safety Reminder
- Key Message: Fluoroquinolones (e.g., ciprofloxacin, moxifloxacin) should only be prescribed as second-line therapy when other antibiotics are inappropriate.
- Serious Risks: They are associated with prolonged, disabling, and potentially irreversible adverse reactions affecting multiple systems.
- Common Reactions: Tendonitis/tendon rupture, peripheral neuropathy, and psychiatric reactions are highlighted. These can occur in patients of any age and without pre-existing risk factors.
- NZ Data: Since 2015, the majority of local reports for ciprofloxacin relate to tendon disorders.
2. MARC’s Remarks: June 2025 Meeting
The Medicines Adverse Reaction Committee (MARC) recommended several data sheet updates:
- Macrolide Antibiotics: Include a class-wide warning about the risk of cardiovascular death.
- Arexvy (RSV Vaccine): Update the data sheet to align with balanced Australian information on Guillain-Barré Syndrome (GBS), noting insufficient evidence for a causal link but a lower risk than from RSV infection itself.
- Nintedanib: Add proteinuria, renal failure, and thrombotic microangiopathy as potential adverse effects.
3. Safety of Medicines for ADHD in Adults
- Context: Increased adverse reaction reports in 2024 and upcoming regulatory changes (Feb 2026) expected to increase access to ADHD medicines.
- Medicines: Stimulants (lisdexamfetamine, methylphenidate) and non-stimulants (atomoxetine).
- Key Safety Considerations:
- Psychiatric: Assess personal/family history; monitor for suicidality, aggression, and tics.
- Cardiovascular: Contraindicated in serious cardiac conditions; monitor blood pressure and heart rate.
- Other: Seizure risk, potential for serotonin syndrome with other serotonergic drugs, risk of abuse (stimulants), and risk of severe liver injury (atomoxetine).
4. Systemic Retinoids and Diffuse Idiopathic Skeletal Hyperostosis (DISH)
- Risk: Cases of DISH (abnormal bone formation in the spine) have been reported with systemic retinoids (e.g., isotretinoin, acitretin), usually after long-term use and/or high doses.
- Onset: Hyperostosis can be detectable on imaging within 6 months but patients often remain asymptomatic until the condition is advanced.
- Management: Disease progression does not appear to continue after stopping the retinoid.
5. Medicine-Induced Pisa Syndrome
- Definition: A rare neurological condition causing involuntary lateral bending of the spine.
- Common Culprits: Most frequently associated with anticholinesterase inhibitors (e.g., donepezil) and antipsychotics.
- Management: The syndrome is often reversible upon discontinuation or dose reduction of the causative medicine.
6. Gathering Knowledge from Adverse Reaction Reports
Presents informative recent case reports, including:
- Hallucinations and psychosis in an elderly patient using a scopolamine patch.
- Bullous pemphigoid induced by furosemide.
- Guillain-Barré syndrome following shingles vaccination.
- Myositis from a drug interaction between simvastatin and itraconazole.
- Achilles tendon pain with isotretinoin.
7. Recent Data Sheet Updates
Highlights important new safety information for several medicines, including:
- Acalabrutinib: Updated dose adjustments and safety data.
- Adrenaline (EpiPen): Warnings about biphasic anaphylaxis and ethanol content.
- Apixaban (Eliquis): Added risk of liver failure.
- Olaparib (Lynparza): Warnings for drug-induced liver injury.
- Paracetamol/Codeine/Doxylamine (Mersyndol): Not recommended with gabapentinoids due to CNS depression risk.
- Salbutamol (Ventolin): Reminder that the inhaler has no dose counter and delivers only 200 actuations.
- Shingles Vaccine (Shingrix): Added Guillain-Barré syndrome as a very rare adverse reaction.
8. Other Sections
- Quarterly Safety Communications: A list of recent safety alerts and Dear Healthcare Professional Letters.
- Recent Approvals: New active ingredient Sacituzumab (Trodelvy) for breast cancer, and new indications for several existing medicines (e.g., aripiprazole for bipolar disorder, upadacitinib for giant cell arteritis).
