Is it permissible (halal) or forbidden (haram) to purchase medicines with an additional free quantity (bonus) from pharmaceutical companies, given the possibility of deducting the value of this bonus from the invoice to reduce the price?

"Bonus" refers to free packs of medicine provided by pharmaceutical companies to pharmacies as an incentive to increase purchases. This is a marketing strategy not exclusive to pharmacies. There is no harm in these incentives; they are in-kind gifts or a reduction in the price of the commodity, and do not involve usury (riba), gambling (qimar), excessive uncertainty (gharar), or deception. The pharmacist must be trustworthy in dispensing medicine, and it is not permissible for him to deceive patients by providing lower quality medicines in order to obtain the "bonus." Rather, he must dispense the prescribed medicine or one that is of better quality and price.