“LIFE IS SO AMAZING!” I thought to myself. I could overhear from the distance someone praying fervently for the rains to come. He had just planted some seeds which required lots of water to grow in the initial stages. The weatherman’s prediction had turned out to be inaccurate! The rains had defied the predictions! Two weeks after the rains were supposed to have started, the best that ever was, were two fine drizzles five days apart. “My seeds will roast in the soil,” he had informed me ruefully. In the front row at the same prayer meeting,another person was praying for a week free of rain because of the funeral ceremonies of her late mother. I shook my head as I remembered the popular adage, “One’s man meat is another man’s poison.” That is life for you! This life!

 So, it was with two gentlemen.  60year old, Mr. Aye presented with a history of progressive difficulty seeing clearly whenever he was out doors especially when the sun was up. The other a 45year old man had difficulty seeing clearly whenever he entered a room even in day time. “I would see the people in the room. Initially, it took one to two minutes to recognise the faces in the room. Now it seems to be getting worse,” he complained. “How long has this gone on,” I asked. I first noticed it about a few months ago,” he replied. “And it doesn’t matter what time of the day, but it’s worse at night,” he added. A few more searching questions, I had a faint idea of what the problem was but I needed to be exact before I could help him. He had been to several places seeking help without any respite. It was getting worse and he was scared he was on his way to blindness.

I got what I didn’t bargain for when I commenced his examination!Before me was a well-fed man, in his forties, apparently in a good state of health with the challenge of adapting to room lighting whenever he came in from outdoors. I hardly expected him to go far on the Snellen’s chart we use for measuring visual acuity. He not only did, he surprised me by reading an extra line with each eye. His visual acuity was 6/5 which was better than normal. That meant he could see at 6meters, what a normal eye should see at 5metres! This provided an indirect evidence that the pathway was intact. My examination confirmed this. The pathway from the cornea, (the ‘glassy’ transparent part of the eyeball) through the lens to the retina (inner coat of the eye) and from there, through the optic nerve to the brain was normal. “Where then is the problem?”

It was obvious I had missed something! What was it? I gradually and silently went through my findings from my interrogation to my examination. The answer hit me. “Eureka!”I nearly exclaimed like Archimedes, when, after a long study discovered a method of detecting the amount of alloy mixed with gold in the crown of the king of Syracuse. I had failed to ask him some vital questions. I had to go back to these questions for therein was the answer. “Have you had a change of lifestyle recently/” “No, Dr Ben,” he responded. “How much alcohol do you consume daily?” “I am a teetotaller,” he replied. I couldn’t believe it! No alcohol at all? Not even occasionally for a man who admitted to smoking two packs of cigarettes daily. “What medications do you take on a regular basis,” I asked again. The answer was devastating. “I take a full course of chloroquine tablets every month to prevent malaria infection. I have been taking it for more than three years!” My face fell. I knew that he had commenced on a journey to irreversible blindness, except technology provided something that could prevent further damage.

Difficulty adjusting to the dark is the earliest symptom of chloroquine retinal toxicity. In many diseases, functional impairment (as evidenced by the symptoms)  occurs before there are noticeable structural changes (signs). Once the vision is affected, rapid deterioration ensues and blindness occurs within five years and it is irreversible. It is painful to watch a patient progress from a very good vision to total irreversible blindness. Excessive use of chloroquine can cause blindness. Use it