What are some common issues or problems with droppers for pharmaceutical bottles?
The most common problems with droppers for pharmaceutical and similar bottles are leakage, poor suction, dripping, teat deterioration, inaccurate dosing, contamination and difficulty opening child-resistant closures. Most of them result from a mismatch between components, an unsuitable material for the liquid, or incorrect use. Knowing them in advance makes it easier to specify the right dropper.
Leakage
Leaks occur when the collar does not seal on the bottle rim. Typical causes are an incorrect thread standard, a damaged or chipped bottle neck, a collar that has not been fully tightened, and overfilling. In transport, pressure and temperature changes may also push liquid past a poor seal, so shipping tests are worthwhile for products sent by post.
Poor suction or no suction
If the teat does not draw liquid, the usual reason is air leaking in through a cracked or loose teat, or a pipette that is too short to reach the liquid. A partly blocked tip can also cause the problem. The length of the pipette has to correspond to the bottle size, for example about 58 mm for 10 ml and 70 mm for 20 ml bottles.
Dripping and uneven drops
Drop size changes with viscosity, temperature and tip design. Thin liquids and solvents drip readily, while thick oils are slow to form. A drop count per ml of around 20 to 30 is typical, but it varies between products and should be checked with your formula, not assumed.
Teat degradation
Teats are elastomers. In contact with certain oils, alcohol or essential oils they may swell, soften, harden or release colour. The material choice is therefore important: NBR and TPE teats behave differently, and a compatibility test on the final formula over its shelf life is recommended.
Inaccurate dosing
A dropper is not a precision measuring device. A squeeze on a 10 to 30 ml bottle draws up only a fraction of a millilitre to about 1 ml, and the amount depends on how firmly the teat is pressed. Graduated pipettes help the user to judge the amount, but dosing instructions for medicines must come from the label or a pharmacist.
Contamination
Touching the tip against skin, eyes or surfaces transfers microbes and residues back into the bottle. Keep the pipette inside the bottle, close the cap after every use and avoid dipping a used dropper into a shared container.
Difficult opening
Child-resistant and tamper-evident collars are deliberately more difficult to open. Clear instructions on the label, such as pressing down while turning, help users who are not familiar with them.
Summary of problems and prevention
- Leakage: check thread, neck finish and fill level.
- Weak suction: check the teat, fit and pipette length.
- Dripping: test the viscosity and drop behaviour.
- Teat damage: run compatibility and stability tests.
- Dosing: use graduated pipettes and clear instructions.
- Contamination: instruct users on hygiene.
Korduma kippuvad küsimused
Why does my dropper leak during shipping?
Pressure, vibration and temperature changes stress the seal. Make sure that the collar is tight, the bottle is not overfilled and outer cartons give adequate protection.
Which teat material is best?
It depends on the formula. Test NBR and TPE with your own product, because compatibility differs between liquids.
Can droppers be used for sterile products?
Standard droppers are not sterile. Products with sterility requirements need a suitable closure and process, and you should seek expert advice.
Choosing droppers for your product
Most of the problems above are avoided by choosing compatible parts from the outset. All Packaging.si droppers use a DIN18 thread and are made in Slovenia under an ISO 9001:2015 quality management system. We can supply samples so that you can test leakage, suction and teat compatibility with your own formula before ordering a full quantity.
