Conclusion:
The relation between Khat chewing and vocal tract tissue reaction leading to oropharyngeal fibrosis and deformities could be proposed with strong relation to the use of pesticides. Further studies are needed to confirm the relation between different types of pesticides and Khat chewing. Wide sample of control group in areas north to Sanaa’ and areas in Sanaa’ or to the west with analysis of the type of Khat in each area and with oro-pharyngo-laryngeal examination of these cases. Strong recommendations to stop using Khat irrigated with Pesticides or at least to wash it carefully to wash out the pesticide remnants. Questions regarding Khat chewing should be involved in clinical history taking especially in immigrants coming from countries famous of using Khat.
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