Synergists
Chemicals that enhance insecticide effectiveness by blocking detoxification enzymes - most commonly PBO in pyrethroid formulations.
Detailed Overview
Synergists have little insecticidal activity alone but dramatically increase effectiveness when combined with insecticides. PBO (Piperonyl Butoxide) is most common synergist - blocks insect enzymes that break down pyrethrins and pyrethroids, making insects more susceptible. Found in most pyrethrin aerosols and many pyrethroid products. Typical ratio: 10:1 PBO to pyrethrin. Without PBO, pyrethrins much less effective. MGK-264 is another synergist used with pyrethrins. Synergist benefits: (1) Increases knockdown speed - insects die faster. (2) Reduces amount of active ingredient needed. (3) Helps overcome some resistance - blocks detox mechanisms insects use to resist insecticides. (4) Cost-effective - synergist less expensive than increasing active ingredient percentage. PCO considerations: products with synergists more effective than those without - check labels for PBO content. Especially important for flushing applications and aerosols where fast knockdown desired. Some resistance in bed bugs and German roaches partially overcome by PBO. Not a substitute for resistance management through MoA rotation, but helpful. Pre-mixed formulations contain synergist at optimal ratio - do not need to add separately.
When to Use
Look for products containing PBO when using pyrethrins or pyrethroids, especially for flushing, aerosols, and situations requiring rapid knockdown. Synergized formulations more effective than non-synergized.
Required Skill Level
Requires some training and experience in pest management
Benefits
- Dramatically increases pyrethrin/pyrethroid effectiveness
- Faster knockdown speed
- Can partially overcome some resistance
- Reduces amount of active ingredient needed
- Cost-effective enhancement
Limitations
- Only works with certain insecticide classes
- Not a substitute for proper resistance management
- Adds some toxicity (though low)
- Pre-mixed products already optimized - separate addition unnecessary
Related Concepts
Other product types that may be useful
Reduced-Risk Pesticides
Low-toxicity pesticide products that pose minimal risk to humans, pets, and the environment while remaining effective against target pests.
Insect Growth Regulators (IGRs)
Pesticides that disrupt insect development and reproduction by mimicking or blocking growth hormones - providing long-term population suppression.
Non-Repellent vs Repellent Chemistry
Understanding the difference between insecticides pests cannot detect (non-repellent) versus those they avoid (repellent) - critical for colony elimination.