BY DR SIMON ONSONGO AND PROF PETER OJWANG
In the recent past many Kenyans have lost their dear lives to illicit brews that have now come to be common phenomenon in this country.
Despite the spirited effort by the law enforcement agencies, many Kenyans still continue to suffer from the direct and indirect complications of illicit brews in various parts of the country.
Some of these brews which go by their traditional names include busaa, changáa, mnazi, kalovo and muratina.
The drinks are readily available in many places in Kenya but more prevalent in the low socio- economic areas where most people cannot afford to buy the commercially prepared drinks available in the market.
Some of the traders who sell these illicit brews lace them with compounds like methanol to make them more potent and to increase their sales volumes.
Methanol is the preferred agent in most cases because it is cheap, readily available in most places and has a similar taste with alcohol hence it is undetectable to the unsuspecting public. So how do these illicit brews lead to the various medical complications associated with them?
Medical complications following consumption of illicit brews commonly arise from the toxic effects of methanol. In its pure form, methanol is a colourless volatile liquid at room temperature with a faint alcoholic smell.
It is readily miscible with water. It has wide applications mainly as an industrial chemical in the synthesis of many substances e.g. dyes, paints, printing and photocopying agents, varnishes, wind shield washer fluid and paint removers.
It is also used in denaturation of ethanol used for industrial uses. Denaturation is a process of adding additives to ethanol to make it poisonous or unpalatable. Denatured alcohol also called methylated spirit attracts less tax hence is cheaper than pure ethanol.
Ingestion of methanol can be unintentional like in unsuspecting alcoholic taking illicit brews laced with methanol or by children who may accidentally ingest the compound.
People who want to commit suicide may also intentionally drink methanol. Rare cases of poisoning have been reported in industries due to prolonged inhalation of methanol fumes or prolonged skin contact especially in industries.
Lethal doses of methanol vary from individual to individual but usually range from as small as 60mls to 500mls of pure solution. It is almost impossible to determine the exact amount of methanol in an individual who has taken illicit brews.
Once ingested, methanol is rapidly absorbed from the gastrointestinal tract usually within 30 minutes but can take up to one hour in individuals who have eaten prior to ingestion. It is worth noting that methanol is metabolised to form toxic metabolites once absorption has occurred from the gut.
The liver is the major site of conversion of methanol to its toxic metabolite, formic acid which is responsible for the various toxic effects seen in poisoned victims. This toxic metabolite takes approximately 20 hours to be eliminated in the urine but this to a great extent depends on the amount of methanol ingested.
The formic acid acts by inhibiting tissue respiration in many tissues but the optic nerve, which is important for vision and the brain are the most affected.
People with toxicity will have symptoms of blindness, some of the affected people might think that the lights have been switched off. Other symptoms may include vomiting, abdominal pain, vomiting, confusion, rigidity, convulsion, altered speech irregular or fast breathing or may even be unconscious in severe cases. A high index of suspicion is critical in the diagnosis of most poisoned people.
Once suspected, an individual must be rushed to a medical facility as soon as possible. In the hospital the main principle of managing poisoned people is to try to reduce the absorption from the gut as much as possible and to reduce the formation of formic acid in the liver.
When found early enough within the first 30 minutes efforts to reduce absorption of methanol for the intestines can be instituted.
There are two main antidotes available in cases of methanol poisoning. One is to give the poisoned patient ethanol either given via the veins or orally.
Ethanol should be readily administered in victims as soon as possible to avert the various complications but needs close monitoring in a good hospital set up to avert various complications associated with ethanol itself.
Ethanol acts by reducing the formation of toxic metabolites from methanol. Remember that an excessive amount of ethanol in circulation is also toxic and may cause damage in various body organs.
The second option is a drug called fomepizole which is better than ethanol but is more expensive and not readily available in most places. For those poisoned people who may take a long time to reach a health facility, taking any ethanol formulation maybe the only way to prevent blindness or stop death.
Other types of alcohols that can cause poisoning include ethylene glycol, diethylene glycol and isopropanol but are rare causes of poisoning in Kenya.
Points to remember about methanol poisoning;
1.Methanol is a toxic compound closely related to ethanol.
2.Methanol is readily available and is fairly cheap industrial product used in the synthesis of many products.
3.Methanol poisoning can be intentional or accidental and can lead to severe complications.
4.Early suspicion of poisoning and early treatment with ethanol or fomepizole may be lifesaving
5.Fomepizole is a better drug in treating methanol poisoning but is not readily available and is expensive.
6.In persons with suspected poisoning, giving the victim any ethanol formulation may avert serious complications especially when health facilities are distant.
(Dr Simon Onsongo and Prof Peter Ojwang work at the Department of Pathology, Aga khan University Hospital Nairobi)