The misidentification of common adverse effects of medication

A paper published in the Journal of the American Geriatric Society entitled “Identifying and quantifying potentially problematic prescribing cascades in clinical practice: A mixed-methods study” throws a sharp light on mistakes that were made by physicians, GPs, hospital staff and epidemiologists during the pandemic.

A prescribing cascade occurs when adverse effects result which are not recognised as caused by the drug; after which another medication is added. In other words, a doctor may believe that the adverse symptoms are caused by a separate illness and then prescribe a new medication on top of the existing one. The study identified a staggering 66 types of commonly prescribed medications which are known to lead to problematic consequences sufficient to generate mistaken prescribing cascades.

The paper lists the medications by their technical name without specifying what they are routinely prescribed for, so here are some of the medications including their use and associated adverse outcomes which are suffered by some recipients.

For example Amiodarone is used to treat fast or irregular heart rhythms like tachycardia or atrial fibrillation. Its serious side effects include a condition known as hypothyroidism (underactive thyroid). Hypothyroidism causes the body’s metabolism to slow down leading to symptoms like fatigue, weight gain, cold intolerance, depression, and dry skin. Doctors often prescribe hormone replacement drugs if this side effect develops as if it were a new unrelated condition, when the adjustment, cessation or an alternative to Amiodarone would have been an appropriate response.

Lithium is prescribed for bipolar disorder, severe depression and aggression but its side effects include tremors, Parkinsonism and hypothyroidism, each of which in their own right can lead to prescribing cascades, when the drug itself is causative rather than a case of a new disease emerging.

Gabapentin is used by around 66,000 people in NZ. Increasingly it is prescribed for chronic pain. A study published in December 2025 entitled “Decision-Making and Downstream Outcomes of the Gabapentinoid-Diuretic Prescribing Cascade” looked at 120 cases of oedema or swelling in the legs due to fluid retention resulting from gabapentin use. In only four cases out of the 120 did the doctors realise that the oedema was a side effect of the gabapentin. In almost all cases a doctor prescribed a diuretic to reduce fluid retention when reductions in gabapentin use or an alternative prescription would probably have greatly resolved the problem. In many cases the doctor who prescribed gabapentin originally was not the doctor who prescribed the diuretic. This is a really concerning statistic which shows how much doctors are divorced from the reality of drug consequences and how much some rely on the advice of pharmaceutical reps and computer-based drug prompts without researching further and updating their knowledge.

In other common cases ACE-inhibitors (used to treat hypertension, heart failure and kidney failure among diabetics, estimated to be taken by 500,000 people in NZ), Beta Blockers (used to control high blood pressure and the eighth most commonly prescribed medication in NZ), and diuretics are all associated with erectile dysfunction in same cases. 

The first study we referenced above found that Statins (taken by 500,000 Kiwis) are known to cause cognitive impairment, erectile dysfunction, heart arrhythmia, insomnia, urinary incontinence, agitation, confused state of mind and depression in some recipients. All of which the study concludes are often diagnosed and treated separately without the doctor realising that statins were to blame. This is all the more concerning because statin prescriptions are routinely given as a preventive strategy based on age rather than for a diagnosed condition.

Half a million NZers are estimated to take antidepressants, the study reports they are known to cause prescribing cascades connected with the development of migraines and Parkinsonism.

Combinations of medicines prescribed to the same person are even more potent sources of further prescribing cascades.

From the above, you can see that doctors are not always well informed about potential side effects of commonly prescribed drugs. No wonder that the majority of physicians and health authorities dismissed as unrelated a range of serious adverse effects experienced by tens of thousands of Kiwis following mRNA Covid vaccination. There is a need for better doctor education about adverse effects of medication and the commonly overlooked prescribing cascades. An automated prompting system to remind GPs of known drug side effects at the time of consultation should be instituted. There should be more awareness of the benefits of reducing the burden of medication especially for older adults.

Doctors need to be trained in an armoury of effective simple first responses like exercise, walking, dietary adjustment, yoga, meditation, breathing exercises, daily routines, along with avoidance of excessive alcohol consumption, smoking, vaping, and other habits negative to health. Prescriptions given out need to be followed up and the health outcomes monitored and if necessary adjusted. With this we could see a big improvement in public health outcomes

NB None of the above information is intended to be advice about any medical condition or prescription you may have been given to maintain your health. Adverse effects described by the above recently published studies are not developed by all people receiving the mentioned medications. If you wish to change or adjust prescription medications, it is important to seek the advice of your GP.

Image credit: Towfiqu Barbhuiya

Guy Hatchard PhD was formerly a senior manager at Genetic ID a global food testing and safety company (now known as FoodChain ID). You can visit his website hatchardreport.com or subscribe to his Substack.

He is the author of ‘Your DNA Diet: Leveraging the Power of Consciousness To Heal Ourselves and Our World. An Ayurvedic Blueprint For Health and Wellness’.