Concomitant treatment, especially acute therapy, with potentially nephrotoxic or myelosuppressive drugs (e.g. systemic pentamidine, dapsone, pyrimethamine, co-trimoxazole, amphotericin, flucytosine, ganciclovir, interferon, vincristine, vinblastine and doxorubicin) may also increase the risk of adverse reactions to zidovudine. If concomitant therapy with any of these drugs is necessary then extra care should be taken in monitoring renal function and haematological parameters and, if required, the dosage of one or more agents should be reduced.
Retrovir Summary of Product Characteristics, Viiv Healthcare UK, Ltd, December 2018.

The effects of dapsone (100 mg once daily) and/or trimethoprim (200 mg twice daily) on single doses of zidovudine (200 mg ) were investigated in 8 HIV-infected subjects. Zidovudine did not influence the pharmacokinetics of dapsone or trimethoprim. Dapsone had no effect on the pharmacokinetics of zidovudine. Trimethoprim significantly decreased renal clearance of zidovudine by 58%, with a concurrent 54% decrease in the mean urinary recovery of zidovudine. The combination effect of trimethoprim plus dapsone on the pharmacokinetics of zidovudine was similar to effect of trimethoprim alone.
Zidovudine, trimethoprim and dapsone pharmacokinetic interactions in patients with human immunodeficiency virus infection. Lee BL, et al. Antimicrob Agents Chemother, 1996, 40: 1231-1236.