A tire can typically be patched multiple times, but the exact number depends on several factors, including the tire's condition, the location of the punctures, and the type of tire. Generally, a tire can be safely patched up to three times, provided the punctures are not too close to each other and are located in the tread area. Patches should not overlap, and the punctures should be at least 16 inches apart. 
Patching is only recommended for punctures in the tread area, not the sidewall or shoulder, as these areas are under more stress and cannot be safely repaired. The size of the puncture also matters; typically, punctures larger than 1/4 inch in diameter are not suitable for patching. 
The tire's overall condition is crucial; if the tire is old, worn out, or has significant damage, it may not be safe to patch it at all. Additionally, the type of tire (e.g., run-flat, high-performance) may have specific guidelines or limitations on patching. 
Ultimately, the decision to patch a tire should be made by a professional who can assess the tire's condition and ensure that the repair will be safe and effective.