Hi and thank you so much for this query. I am Dr. Ditah and feel honored having this opportunity to address your health questions. I am so sorry to hear about this diagnosis of Glioblastoma Multiforme in your dad.

The treatment of Glioblastoma is a combination of surgery, chemotherapy(anti cancer drugs) and radiotherapy(destroying cancer cells with x-rays) depending on its location and the stage(whether it is localised or spread to other areas of the body) of the tumor. Dexamethasone and bactrim forte are not the main stay of this treatment but may be necessary to treat or prevent infections (Bactrim) or reduce the oedema caused by this tumor. My best guess is that you father has another reason why he was prescribed these drugs. They were not prescribed to treat the tumor but to prevent or treat a bacteria infection(Bactrim) and the dexamethasone to reduce oedema around the tumor to relief him of some of the symptoms of brain swelling..
Also, you may want to ask his doctor what were the specific reasons for the drugs she/he prescribed.

If this is the only treatment the doctor has proposed to your dad, then it is definitely not the treatment for this tumor type. However, if it is for some other reasons, then I think he is correct. Talk to him and understand what are the reasons she/he chose to and what is his treatment plan for this tumour your dad has.

I hope I answered your query fully. If there are any follow up questions related to this query, please feel free to contact me. I am more than happy and ready to address them.
I wish your dad the best possible outcome as he takes on the fight against this cancer. I will also advice that you all stand by him and show him how much you all love him so as make it a less difficult task for him. He will need so much of this.
Once more, thank you so much for using our services.
Dr. Ditah, MD.

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