Latex allergies are more common than you might realize. Hold the water in your ass for a few seconds, then relax and release it into the toilet. The lower part of the colon will be cleanest after a bowel movement, so knowing your body and being regular—fiber, fruits and veg, water that you drink, not pump up your butt —is often enough. The volume is also smaller so you are less likely to overdo it. This method is particularly popular among gay men. These require you to be extra careful with your douching.
Steer clear of injection drugs.
Savage Love Letter of the Day: A Two-Hour Douche
When I finally tried to carry out these fantasies, I could not take anything bigger than a pinky finger. There is no magic number of times that makes douching unsafe. If you douche too often with tap water, you can cause an electrolyte imbalance that using normal saline would prevent. My sex life did not really begin until a friend told me he has a latex allergy and suggested maybe that was my problem as well. When I get fisted, I use non-latex gloves. Silicone lubricants are a popular choice because they last longer than water-based, but both types are compatible with condoms unlike oil-based lubes. If you are able to carry a douche or enema with you, you might want to at least do a squirt after you take a hit.
But I must also stress that if you have smart, sane, and consensual sex, and only push your limits within reason without exceeding your abilities, you can enjoy bottoming for years without problems. By far the most commonly cited piece of advice was to be careful and take your time. But since that bulb douche clearly isn't working for you, the next step would be a shower douche. Not only is getting fisted a sensory overload, but it requires more trust and vulnerability than perhaps any other sex act with the exception of various kink and BDSM scenes. Most people said they use water. Other bulking agents like fiber supplements are OK to take.