Bitter kola nut extract, promising eye drop for glaucoma, apollo

By Sade Oguntola - updated: Thursday 18-06-2009

Bitter kola nutScientists have found strong evidences suggesting that bitter kola nut water extract holds promise for treatment of glaucoma, a group of eye diseases that damage the optic nerve and can result in serious vision loss over time.

One of the main causes of glaucoma is high eye pressure that is caused by the build up of natural fluid produced by the eye. High eye pressure occurs when drainage channels in the eye are blocked. This pressure damages the optic nerve, the “cable” used by the eye and the brain to communicate. The damage to the optic nerve is permanent, and it can cause loss of vision.

As many as half of individuals with glaucoma, however, may not know that they have the disease. The reason for this is that glaucoma initially causes no symptoms, and the loss of vision on the side (periphery) is hardly noticeable.

In a new study to determine the effectiveness of bitter kola nut extract drop on the eye, the scientists said that the effectiveness of bitter kola nut water extracts’ in reducing the internal pressure in the eye is similar to that achieved using commonly prescribed glaucoma medications.

The multi-centre open study involved 106 adults’ volunteers from three Nigerian Ophthalmologic centres in the Lagos University Teaching Hospital, Lagos; Obafemi Awolowo University Teaching Hospital and Ahmadu Bello University Teaching Hospital, Zaria as well as Olabisi Onabanjo University Teaching Hospital, Sagamu, Ogun State.

In the 2008 study published in the Nigerian Postgraduate Medical Journal, the researchers applied drops of bitter kola nut water extract into the right eyes of the participants and then measured the resultant effect at baseline, 15 minutes, 30 minutes and 45 minutes while the left eye of each of the participants served as the control.

The study, which excluded people that had eye problem and medical conditions such as cataract, diabetes mellitus, eye injury and previous eye surgery, found that the effect of the eye drop made from bitter kola nut water lasted for 45 minutes , with waning effect noticeable afterwards.

Earlier research on laboratory animals’ eyes had demonstrated that bitter kola nut water extract was able to correct abnormal constriction of the pupil of the eye which makes the eye smaller as well as reduces intraocular pressure in the eye; thereby opening up a new vista on the claim by African traditional medicine that it was a safe and effective substance in the control of open angle glaucoma, the commonest type of glaucoma that affects black people.

The bitter kola nut water extract, the study led by Dr. A. O Adefule-Ositelu from the Lagos University Teaching Hospital suggested, may have helped to ensure reduction in production and emptying of the clear fluid called the aqueous humor, which provides nourishment to the structures in front of the eye.

The process of producing and removing the fluid from the eye is similar to that of a sink with the faucet always turned on, producing and draining the water. If the sink’s drain becomes clogged, the water may overflow. If this sink were a closed system, as is the eye, and unable to overflow, the pressure in the sink would rise.

Likewise, if the flow of eye fluid becomes clogged or blocked, the intraocular pressure may become elevated. Also, if the sink’s faucet is too high, the water may overflow. Again, if this sink were a closed system, the pressure within the sink would increase. Likewise, if too much fluid is being produced within the eye, the intraocular pressure may become too high.

In either event, since the eye is a closed system, if it cannot remove the increased fluid, the pressure builds up and nerve damage results.

Previous studies in the 2007 edition of the journal, The South African Optometrist, that involved young people attending the Abia State University Optometry Clinic, Uturu, also has similar results. The particiapnts in this Uturu study were made to chew and swallow bitter kola nuts as bolus. Their finding was that its consumption also showed the same effects on the intraocular pressure in the eye, after 45 minutes of its ingestion, in a dose dependent fashion.

According to the results obtained from this study, ingestion of bitter kola nuts produced a decrease in the pupil size and a drop in the intraocular pressure, thus improving vision and intraocular eye pressure.

Meanwhile, the scientists said more collaborative studies on the effects of bitter kola nut water extract on intraocular pressure and loss of vision are presently going on to further demonstrate the usefulness of the natural plant product.

This is particularly so because the local discovery of a drug that will lower the intraocular pressure will solve the problematic difficulties encountered in the management of glaucoma, a common cause of preventable blindness, moreso, for cheaper purchase, availability and improved morbidity.

The usefulness of bitter kola nut water extract to treat viral eyes such as conjunctivitis, which is commonly referred to as Apollo, was documented by the same researchers in 2004 in the Nigerian Quarterly Journal of Hospital Medicine.

The finding of the study carried out at the Guinness Eye Centre of the Lagos University Teaching Hospital (GEC/LUTH was that as early as two hours, most patients remarked that they got relief from most of their eye symptoms, while within six hours of commencing treatment, most patients confirmed this relief.

The effectiveness of this extract to quickly bring resolutions to the symptoms and signs of these patients with red eyes, because of its antimicrobial properties, they said, is noticeable and encouraging, adding, “since no specific anti-adenoviral agent is presently in existence globally, this may serve as a breakthrough in the management of these viral infections.”

In the meantime, bitter kola nut has been found useful in the treatment of head and chest cold, colic, improves singing voices through soothing effect on vocal cords and relieving coughs and hoarseness of voice. The fresh seed is also chewed as an aphrodisiac while the dried seeds are used in the treatment of dysentery and diarrhoea.

Further indications for bitter kola nut include stoppage of bleeding after childbirth and infections of the urinary tract and quite recently, the water extracts of bitter kola nut was shown to possess anti fungal activities that make it useful in treatment of eye infections that are of fungal origin.

Sometime, people chew its fruit pulp to clean the mouth of germs and in the treatment of cuts and sore throat. The roots and stem which serve as bitter chewing sticks are also used for oral hygiene.

The latex obtained from the stem bark of the bitter kola nut plant has been reported to be effective against parasitic skin diseases when applied directly as a wound dressing.

Bitter kola nuts are also used to prevent arthritis while the seeds are used for the treatment of liver disorder and as a possible substitute for hop in the beer industry.