No, you should not drink alcohol while taking sulfamethoxazole / trimethoprim tablets, or else you may experience unpleasant side effects such as fast heartbeats, warmth or redness under your skin, tingly feeling, nausea, and vomiting.

Drinking any amount of alcohol can result in such side effects . Keep in mind that some cold medicines and mouthwashes also contain alcohol. So check the label and avoid if alcohol is present.

The effects of combining antibiotics and alcohol can vary, depending on the specific antibiotic. Alcohol does not diminish the effectiveness of most antibiotics.
However, there are certain antibiotics which should not be combined with alcohol because of a drug interaction.
Trimethoprim-sulfamethoxazole is one of these.

https://www.drugs.com/interactions-check.php?interaction_list_id=183138729&drug_list=2128-0,1034-14582

https://www.drugs.com/article/antibiotics-alcohol.html