Overview

There is a lot of potential in the use of herbal supplements to improve certain health conditions. Thus, research is always ongoing to ensure the benefits of these herbal supplements are harnessed to improve the quality of life. Tinnitus is not an exception as it is prevalent in a lot of adults, particularly in people 60 years and above.¹ This condition is not a disease but rather, it is a symptom of a plethora of underlying conditions. First, let’s cover some basics of tinnitus. 

What is tinnitus?

Tinnitus is a symptom that occurs when someone experiences the perception of one or more sounds in the ears or head without an external source of sound. Tinnitus can affect personal, professional and leisure activities. It can disrupt family and social relationships, and in extreme cases, lead to depression and suicide.² 

Tinnitus can be a symptom of severe middle ear problems such as infection, a hole in the eardrum, an accumulation of fluid or stiffening (otosclerosis) of the bones of the middle ear. Tinnitus can also be a symptom of a head and neck aneurysm or acoustic neuroma. Either of these can be life-threatening. 

Tinnitus can also be categorized into three broad groups: mild, moderate, and severe chronic tinnitus. Mild tinnitus does not interfere noticeably with everyday life, moderate tinnitus may cause some irritation and may be perceived as unpleasant, while severe chronic tinnitus affects a person’s entire life. These classifications depend on the individual’s personal description of tinnitus.⁶ 

Types of tinnitus

The following are some types of tinnitus; 

• Objective tinnitus: This is caused by sounds generated somewhere in a patient’s body. This type is uncommon and is characterized by noise in the patient’s ear, which can be heard by an examiner using a stethoscope.⁴ Objective tinnitus can be caused by Eustachian tube dysfunction, carotid artery stenosis and aortic stenosis.
• Subjective tinnitus: This is the perception of incomprehensible sounds without any physical sound actually being present. It can occur with almost any ear disorder or infection, and the sounds can only be heard by the patient. Generally, subjective tinnitus has no physical signs, and there are no clinical diagnostic tests that can differentiate between the different forms of subjective tinnitus. Hence, only the patient’s personal description can form the basis for a clinical evaluation⁶
• Somatosensory tinnitus: This is a form of subjective tinnitus that occurs as a result of a somatic disorder (head or neck disorder, problems with the musculoskeletal system rather than the ears)¹³
• Pulsatile tinnitus: This is a type of tinnitus whereby the patient hears rhythmical noises that beat at the same rate as the heart. Also, the patient’s pulse beats at the same rate as pulsatile tinnitus. It can be triggered by a change in blood flow in the blood vessels close to the ear
• Auditory hallucinations: These are perceptions of meaningful sounds, such as music or speech³
• Sometimes, there is no known cause of the tinnitus. This is referred to as idiopathic tinnitus.

Risk factors of tinnitus

Tinnitus occurs as a result of damage to either the peripheral or central auditory nervous systems. However, the exact cause hasn’t been concretely identified. The following are the risk factors that can lead to this condition:

• Loud noise
• Ear infections
• Head or neck injuries
• Ototoxic drug use
• Hypertension
• History of arthritis
• Smoking and alcohol intake
• Presbycusis (age-related hearing loss): The process of ageing is not a risk factor on its own. Rather, the deterioration of hearing that comes along with getting older poses a great risk⁵

Medical conditions linked to tinnitus

Tinnitus has been associated with the following health conditions:

• Temporomandibular dysfunction: Temporomandibular joint dysfunction (TMD) is a collective term encompassing a wide range of joint and muscle problems in the orofacial area. These disorders are characterised by pain in the joint, unusual sounds, and irregular mandibular function²
• Cardiovascular diseases: Acute noise exposure leading to tinnitus can raise systolic and diastolic blood pressure, change heart rate, and trigger the release of stress hormones.⁷ This ultimately leads to hypertension, myocardial infarction, and other chronic diseases triggered by the release of stress hormones
• Mental health disorders: The American Tinnitus Association reports that “the effects of chronic tinnitus, together with other comorbidities, can tip the scales and lead to emotional health issues”
  
  Additionally, symptoms associated with Post-Traumatic Stress Disorder (PTSD) have been observed to exacerbate in patients with tinnitus. Also, another association relates to the medication used in both disorders. ⁸ Selective serotonin reuptake inhibitors (SSRIs) are the frontline treatment options for PTSD. Thus, as both disorders share similar biochemical stimuli, this medication may affect them in similar ways. Another study implies that tinnitus can be a significant contributor to the symptoms of PTSD. This
  is because they are caused by past traumatic events, which include loud noises such as gunfire and explosions⁸
• Autoimmune disorders: Autoimmune disorders, such as systemic lupus erythematosus, can cause tinnitus. According to the National Institutes of Health, peripheral auditory dysfunction can cause changes that eventually lead to tinnitus in people with autoimmune diseases.
• Diabetes and hyperinsulinemia: Hyperinsulinemia, also known as insulin resistance, is a predisposing factor for type 2 diabetes. However, these conditions can also cause tinnitus. This is because disruptions in glucose delivery and metabolism to the inner ear can interrupt the functioning of the cochlea and vestibular system of the inner ear. This can result in tinnitus and Meniere’s disease.

Red flags indicative of a serious underlying cause of tinnitus

The following are some red flags associated with tinnitus that could indicate a serious health condition;

• Unilateral tinnitus
• Pulsatile tinnitus
• Hyperacusis
• Sudden onset hearing loss
• Vertigo/Dizziness
• The pressure of fullness in one or both ears
• Associated unilateral hearing loss
• Suicidal ideation

Overview of ginkgo biloba

Ginkgo biloba is a widely diversified and valuable plant that has been investigated to confer a variety of health benefits. The name “Ginkgo” is a Japanese word, while its characteristic two-lobed leaves are attributed to the term "biloba." Ginkgo seeds and leaves have been recognized in Chinese medicine and beyond for their therapeutic and medicinal properties, respectively.⁹

The plant contains bioactive compounds, which include organic acids (e.g., ginkgolic acid),
flavonoids (e.g., quercetin, isorhamnetin), bioflavonoids (e.g., ginkgetin, isoginkgetin), and terpenoids (e.g., ginkgolides, bilobalides), with extended applications in various biological systems.¹¹ However, the main phytoconstituents present in Ginkgo biloba, namely flavonoids (ginkgo-flavone glycosides), terpenoids (ginkgolides A, B, C, J, and bilobalide) and ginkgolides are responsible for its therapeutic potency and effectiveness.⁹

How ginkgo biloba is used for tinnitus relief

Several allopathic drugs, such as anti-inflammatories, antidepressants, muscle relaxants, calcium channel blockers, anticonvulsants, and drugs that promote blood circulation around the cochlear region and brain, have been used for the clinical management of tinnitus.¹⁰ These drugs, besides increasing the economic burden, have several severe side effects.¹⁰ Thus, an alternative method such as phytotherapy has been studied for tinnitus treatment. Among the frequently
used medicinal plants, Ginkgo biloba has been investigated in various studies to provide relief for tinnitus.^{12, 13}

According to a study published by the International Tinnitus Journal, Ginkgo biloba can effectively improve patients with tinnitus caused by ischemia due to its myricetin and quercetin flavonoids and ginkgolide and bilobalide terpenoids.¹⁰ Additionally, Ginkgo biloba has antiplatelet and vascular modulator functions. That is to say, it improves blood flow and effectively regulates vascular function. Vascular issues are one of the causes of pulsatile tinnitus, originating from the area of the cochlear nerve cortex.¹⁰ The alterations in the vascular system affect the blood supply to the labyrinthine artery, which in turn causes hypoxia in the outer hair cells of the cochlea and leads to tinnitus. Supplementation with Ginkgo biloba has been reported to enhance adequate blood supply to the cochlea.¹⁰

Commercial uses and other applications

Ginkgo biloba leaves are used in traditional Chinese medicine to provide relief for various neurological problems, circulatory disorders, and respiratory diseases. G. biloba leaves can also be used as insecticides and fertilisers. G. biloba leaf extracts are used as food additives due to their medicinal benefits. Historically, Ginkgo nuts have been used to treat coughs, sputum, fever, diarrhoea, toothaches, skin diseases, gonorrhoea, and overactive bladder. Ginkgo nuts have also been consumed as a side dish in China.¹¹

Additionally, Ginkgo biloba has been studied to confer multi-medicinal and pharmacological activities attributed to its various bioactive compounds. These include a remedy for a variety of respiratory diseases, an anticancer effect, an anti-obesity effect, an antidiabetic effect, an anti-inflammatory effect, etc.¹¹

Other remedies for tinnitus

Other approaches, apart from the use of medication, have been proposed for tinnitus management. These include counselling, habituation therapies, tinnitus retraining therapy (TRT), cognitive behavioural therapy (CBT), tinnitus maskers, mindfulness meditation, and the use of hearing aids. TRT, which is a form of counselling alone or in combination with CBT, can reduce negative reactions to tinnitus. However, specific treatment or management can vary depending on the underlying cause and severity. This is because one treatment cannot be effective for people suffering from tinnitus.¹²

Summary

Tinnitus is a challenge for a lot of people as it affects the quality of life in various ways. However, due to the heterogeneous nature of tinnitus, the combination of treatment strategies targeting diverse pathogenetic mechanisms and active management of comorbidities is required for the effective management of tinnitus.¹³ Ginkgo biloba is one of the most widely researched herbal remedies for tinnitus management. Nevertheless, it is still crucial to understand the underlying cause of tinnitus as this will determine the best technique for its management.