Damien O’Brien MPSI on the different types of fatigue and how patients can get back on the road Ito recovery
Introduction
Fatigue is a common complaint encountered in both primary and secondary care. It is a complex and multifaceted symptom characterised by a persistent sense of exhaustion or lack of energy. Fatigue often persists despite usual strategies for restoring energy and can impair an individual’s ability to carry out their daily activities. Although often equated with tiredness, fatigue is a more complex and multifaceted condition. It may be both a symptom and a syndrome, often without a clear organic cause, and can have a significant impact on daily functioning, productivity, emotional wellbeing, relationships, and quality of life.
Fatigue can be broadly described as physical, mental, or emotional in nature. Physical fatigue involves muscle weakness, reduced physical performance, and low stamina. Mental fatigue is marked by decreased cognitive functioning, such as difficulty concentrating and memory issues. Emotional fatigue is characterised by low motivation and apathy. This article aims to explore fatigue from a pharmacist’s perspective — discussing its classification, causes, evaluation, pharmacological management, and non-pharmacological interventions. The role of the pharmacist has extended beyond medication dispensing to include the assessment and management of symptoms, ensuring a holistic approach to patient care.
Fatigue can be broadly categorised into acute fatigue and chronic fatigue. Acute fatigue is generally self-limiting and often results from identifiable causes such as overexertion, temporary sleep disturbances, or acute illness. Chronic fatigue is defined as persistent fatigue lasting longer than six months. It may be indicative of chronic medical conditions or psychological disorders.
Aetiology
The aetiology is multifactorial, encompassing a wide range of physiological, psychological, environmental, and lifestyle factors.
Understanding the root cause is important in managing fatigue effectively.
Medication-induced fatigue
Many medications list fatigue as a known adverse effect. Beta-blockers decrease cardiac output, which may result in reduced energy levels. Sedative drugs, including antihistamines, antidepressants, benzodiazepines, antipsychotics, opioids, and anti- Parkinsonian drugs, have central nervous system depressant effects and may cause fatigue. Chemotherapeutic agents can induce fatigue through various mechanisms, including anaemia and effects on the central nervous system. Substance abuse disorders, including alcoholism, may also contribute to fatigue.
Pharmacists are uniquely positioned to identify medication-induced fatigue during routine medication reviews. They can collaborate with other healthcare professionals to deprescribe, adjust dosages, or switch medications when appropriate.
Physiological causes
Fatigue is often secondary to an underlying medical condition, with many chronic medical conditions being significant contributors. Both type 1 and type 2 diabetes can lead to fatigue due to fluctuating blood glucose levels. Other endocrine disorders, such as hypothyroidism, often cause fatigue, as slower metabolic processes can reduce energy levels.
Anaemia is a common cause of fatigue, in which the body lacks sufficient red blood cells, leading to reduced oxygen delivery to tissues. Anaemia may result from iron deficiency, vitamin B12 deficiency, or chronic conditions such as kidney disease. Heart conditions, including congestive heart failure and coronary artery disease, may also contribute to fatigue due to impaired oxygenation and nutrient delivery. Sleep apnoea can lead to poor- quality sleep and persistent daytime fatigue. Chronic infections, such as hepatitis, human immunodeficiency virus (HIV), and tuberculosis, can also cause systemic fatigue.
Chronic fatigue syndrome (CFS) is a complex, debilitating disorder characterised by persistent fatigue
that is not alleviated by rest and is worsened by physical or mental activity, significantly impairing daily functioning and quality of life. The exact aetiology is unclear, but a combination of
factors — including immune system dysregulation, viral infections, and stress — may play a role. Patients typically present with persistent fatigue, unrefreshing sleep, post-exertional malaise, and cognitive impairments.
Additional symptoms may include orthostatic intolerance, muscle pain, and headaches. Diagnosis is typically clinical, based on patient history and symptoms, as there are no definitive laboratory tests, and the exclusion of other medical conditions is essential.
Psychological factors
Fatigue often arises from psychological origins, overlapping with mental health conditions such as depression, anxiety, and stress-related disorders.
It is often one of the presenting symptoms of depression, with patients experiencing persistent low energy, reduced cognition, and low motivation, regardless of levels of physical activity.
Anxiety disorders may present with sustained hyperarousal and sleep disturbances, leading to daytime fatigue. Chronic stress, whether from personal trauma or burnout, can result in hormonal imbalances that manifest as physical exhaustion.
Lifestyle and environmental factors
Fatigue is often influenced by modifiable lifestyle and environmental factors that can be addressed to improve energy levels and overall wellbeing. Leading a sedentary lifestyle is associated with increased fatigue. Inadequate nutrition can contribute to fatigue, with a high intake of processed foods and a low intake of fruits and vegetables leading to nutritional deficiencies. Furthermore, excessive alcohol consumption and smoking have been linked to increased fatigue levels. High caffeine intake can also impair sleep quality and energy levels. Sleep quality is another important factor: Poor sleep hygiene, irregular sleep patterns, and insufficient sleep duration can all contribute to persistent fatigue.
Assessment and diagnosis
Accurate assessment of fatigue involves a comprehensive evaluation of the patient’s medical history, medication regimen, lifestyle, and psychological state. Detailed medication reviews are important for identifying potential medication-related causes of fatigue. History-taking and
Pharmacists are uniquely positioned to identify medication- induced fatigue during routine medication reviews
physical examination should focus on identifying common secondary causes, as well as life-threatening conditions such as cancer. Laboratory testing is useful to assess for anaemia, thyroid dysfunction, and other conditions.
Women of childbearing age should undergo a pregnancy test. Standardised assessment tools can help quantify fatigue levels and monitor response to treatment.
Pharmacological management
Pharmacological treatment of fatigue should be personalised, focusing on addressing underlying conditions and providing symptom relief. Its management necessitates a comprehensive approach. While non-pharmacological interventions remain the cornerstone of treatment, pharmacological options can play an important role in alleviating fatigue when tailored to each patient’s needs. A cautious approach is often warranted due to the limited efficacy and potential risks associated with certain medications.
In the case of CFS, the National Institute for Health and Care Excellence (NICE) guidelines emphasise a cautious and individualised approach to pharmacological interventions. The use of medication as a curative treatment is discouraged. Pharmacological strategies focus on symptom management, taking sensitivities and potential adverse effects into account. Starting medications at lower doses and titrating slowly is recommended to enhance tolerability. Antidepressants can play an important role in the treatment of fatigue in certain cases, particularly where it coexists with mood disorders. Selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), and other antidepressants may alleviate fatigue by addressing underlying depression or anxiety. However, the effectiveness of antidepressants specifically on fatigue symptoms is uncertain, and they should be used only following a comprehensive evaluation of the patient’s mental health status.
Central nervous system stimulants, including modafinil and methylphenidate, are sometimes
used to reduce fatigue, particularly in conditions such as multiple sclerosis and cancer-related fatigue. These drugs promote wakefulness and enhance cognitive function. However, evidence for their efficacy is mixed, and there is potential for adverse effects such as insomnia and cardiovascular complications. Their use is off-label and not recommended in the NICE guidelines for routine fatigue management.
Corticosteroids, such as dexamethasone, are occasionally used to provide temporary relief from fatigue, particularly in cancer patients. However, long-term use is discouraged due to adverse effects, including immunosuppression, osteoporosis, increased infection r isk, and adrenal insufficiency.
Non-pharmacological management
There are a range of non- pharmacological interventions that are important in the management of fatigue. In some cases, they may offer a low- cost treatment option that can be used as monotherapy or in combination with pharmacological treatment.
Cognitive behavioural therapy
Cognitive behaviour therapy (CBT) is an evidence-based approach that addresses the psychological aspects of fatigue. It has effectiveness in reducing fatigue symptoms in various conditions, including CFS, depression, and anxiety. CBT helps identify and modify maladaptive behaviours that may contribute to fatigue. Patients can develop coping strategies, improve sleep patterns, and reduce fatigue using this method. NICE guidelines state that CBT is not curative for CFS but may support patients in managing their symptoms, improving functioning, and reducing distress.
Sleep hygiene
Sleep hygiene refers to behavioural and environmental practices that promote high-quality sleep. Promoting good sleep hygiene is crucial in managing fatigue. This involves maintaining a regular sleep schedule, creating a restful sleep environment, limiting screen exposure in the evening, and avoiding stimulants before bedtime.
Poor-quality sleep is a major contributor to daytime fatigue, and small improvements in sleep quality can significantly impact energy levels and cognitive performance.
Nutrition and hydration
Optimising nutrition and hydration are fundamental in managing fatigue, especially when underlying deficiencies are contributing factors. A balanced diet rich in whole grains, lean protein, fruits, and vegetables provides essential nutrients that support energy metabolism. Deficiencies in iron and vitamins often cause fatigue and should be assessed and corrected where necessary. The intake of nutrient-dense foods and, when appropriate, supplementation can help address these deficiencies. This is emphasised in the NICE guidelines, and referral to a dietitian may be required in certain cases.
Coenzyme Q10 (CoQ10) is a mitochondrial cofactor involved in adenosine triphosphate (ATP) production and may play a role in reducing fatigue. Studies have shown that CoQ10 supplementation is effective and safe for alleviating fatigue symptoms, with greater benefits observed at higher doses and with longer treatment durations. Doses typically range from 100mg to 200mg daily, and adverse effects are rare, though mild gastrointestinal discomfort may occur.
Hydration is also vital in the management of fatigue. Even mild dehydration can impair physical performance, cognitive function, and mood, thereby exacerbating feelings of fatigue. Ensuring adequate fluid intake supports optimal physiological function and energy levels. Fluid intake should be individualised based on personal needs, activity levels, and environmental conditions.
Role of the pharmacist
Fatigue is a multifaceted and complex condition, requiring a multidisciplinary approach to management. Pharmacists are accessible healthcare professionals who play a critical role in identifying contributing factors, optimising pharmacological management, and guiding non- pharmacological interventions. They may identify and mitigate drug-induced fatigue by adjusting dosages, switching medications, or deprescribing when appropriate.
Pharmacists may also help manage fatigue symptoms using over-the-counter options, including iron, vitamin B12, or caffeine supplementation. Additionally, they can counsel patients on lifestyle modifications and emphasise the importance of adherence to prescribed treatment plans.
Pharmacists collaborate closely with other healthcare professionals to develop comprehensive care plans that address the multifactorial nature of fatigue, ultimately helping individuals manage and overcome fatigue to improve their overall health and quality of life.
References available on request
