Hi, Two months ago my doctor took me off Bactrim as it was lowering my WBC and platelets, causing my CD4 to halve. My CD4 is now at 105, was 50 before. So, the doctor demonstrated that Bactrim was supressinmg my immune system. I'm afraid of catching PCP without Bactrim but the doctor says that my HAART will protect me. Is he right or should i really be taking some prophylaxis regardless of what it might do to my CD4? Many thanks.

Hello and thanks for your post.

Occasionally, Bactrim (Septra, Cotrimoxazole) can cause suppression of blood cell counts, resulting in anemia, low WBCs (leukopenia) or low platelets (thrombocytopenia).

One way to verify if this your case is to see if your CD4 percentages have remained relatively constant with declining absolute CD4 counts. One would expect as well, that your total WBC count to be lower now than in the past.

Stopping Bactrim in the case of toxicity is reasonable, though your doctor should be considering using an alternative PCP preventive medication, such as atovaquone or Dapsone.

I hope this helps, BY