Is it like a metallic taste? I don't know what poison tastes like so i can't imagine if it is a metallic taste check your throat ( get a flashlight and stand in front of a mirror) by the dangly bit (uvula) are there red, slightly puffy lumps (tonsils) ? Or does your throat look really red? I had the same taste ever since I was 4 and it progressed into tonsillitis and eventually I got them taken out (after 10 years of waiting) if not then see your doctor, you may have a bacterial infection
Have you been on antibiotics recently? Thrush can give you a bad taste in your mouth. Thrush is a yeast infection of your mouth ( mucosa). It occurs if the microorganisms in your mouth are out of balance. It first develops as a white coating on your tongue that can't be brushed off. Then the tongue turns red and beefy like it is inflamed, and if not addressesd for a long time, it turns dry and cracked (fissured). Doctors are good at identifying thrush when it is a white coating but don't always diagnose it once it gets to the inflamed stage. Treatment if usually nystatin ( a liquid medicine that you coat your mouth and the swallow to coat your throat) or diflucan that is a tablet. Nystatin tends to stir up the microorganism in your mouth and it ends up tasting like you just licked a dumpster. Avoid drinking or eating for about 5 minutes after the medicine to give it a chance to work. Take as directed until all the medicine is gone like you would if you would if you were taking an antibiotic. Always take a probiotic when on antibiotics. Culturelle is the most common one but it is expensive and I use a store brand that works just fine. I take it daily since I am prone to thrush. Yogurt is a food source of these good bacteria.