A sting on the paw is a 48-hour problem. A sting on the muzzle or throat is a 15-minute problem. Between June and August, when balcony nests are being built and the afternoon sits at 30-35 C, the gap between the two is a 5-minute weekly check and a 10-minute assessment. Neither needs a specialist; both need a timer.
Why Wasps Choose Balconies
A queen waking at 10-12 C in spring wants shelter, an 8-10 mm gap and morning sun, and a balcony railing offers all three. The first workers appear 7-14 days after the nest is started, and by late August a colony holds 200-5000 of them, all using one entry hole. Balcony humidity of 60-80% in July keeps the paper from drying out and cracking. Wasps defend roughly 2 m around that hole, so the cat sleeping under the railing is inside the defended zone every afternoon.
The 3-Point Balcony Check
Check 3 places once a week from June 1 to September 30. The pass takes 5 minutes with a flashlight, standing 2 m back and looking up first, because two of the three sites are overhead.
Point 1 is the underside of the railing within 30 cm of a corner, where two surfaces meet and rain never reaches. Point 2 is the ceiling corner above the balcony door, the warmest and most sheltered spot on most balconies. Point 3 is ground level: a planter drain hole, the gap behind an air-conditioning unit, the fold of an awning. Nests start at 2-10 cm in all 3.
Go before 08:00 or after 20:00, when the colony is inside and the air is under 20 C; at 15 C a wasp moves slowly enough to be seen and avoided. Never spray at midday, when 30 returning workers in 10 minutes is the usual result.
The First 10 Minutes After a Sting
A honeybee leaves a 2-3 mm stinger with a venom sac that keeps pumping for 45-60 seconds. Scrape it off with a card edge inside that minute. Pinching squeezes more venom in. A wasp leaves no stinger, so there is nothing to remove and nothing to press.
Then measure the paw with a soft tape at the widest point, write the number down, and repeat at 10 and 60 minutes. A normal front paw is 3.5-4.5 cm across; 6 cm at 10 minutes is a different case from 4.5 cm. Photograph it at 0, 10 and 60 minutes with the tape in frame, because 3 photos answer what a phone call cannot.
Watch the walk, not just the paw. A cat that bears weight at a walk is in the mild group. A cat that holds the leg up and stops after 3 steps needs the cold pack and a 24-hour check.
Cold Pack: 10 Minutes On, 10 Off
Use a gel pack at 4-8 C wrapped in a thin towel, never straight from the freezer. Ten minutes on, 10 off, 3 cycles in the first hour, then 2-3 sessions a day for 24-48 hours. Continuous cold narrows vessels so far that swelling rebounds when it stops, and most cats tolerate 10 minutes but refuse 20. Dry the paw afterward; a damp paw between toes at 30 C invites fungus, and ointment only gives the cat something new to lick.
Sting Timeline and What to Do
| Window | Task | Target number | Call the vet at |
|---|---|---|---|
| 0-10 minutes | Scrape stinger, measure paw | 1 scrape, 3 photos | 6 cm paw width |
| 10-60 minutes | Cold pack, on and off | 10 on, 10 off, 3 cycles | Swelling 2x normal |
| 1-6 hours | Peak swelling, weight bearing | 1 check per hour | 6 cm or 3 hops |
| 6-24 hours | Limping and licking | 3 checks per day | 0 weight at 6 hours |
| 24-72 hours | Itching, residual swelling | 2 cold sessions a day | Growing at 24 hours |
Face, Throat and Mouth Stings
Muzzle swelling can close a nostril in 10-15 minutes, and a sting on the tongue closes the airway faster. Drooling, a hoarse mew, noisy breathing, 40 or more breaths a minute at rest, pale gums or pawing at the mouth: leave immediately and call from the car. Anaphylaxis usually develops 5-30 minutes after the sting, so the window is minutes. Keep the carrier level and give nothing by mouth. A human antihistamine dose is wrong for a 4 kg cat and sedation hides the breathing change you need to see.
Five Stings, Kittens and Repeat Reactions
One sting is local. Five or more is a body-wide venom load and needs a same-day exam even if the cat looks fine; 10 or more, or any sting in a kitten under 6 months, is an emergency. A cat that reacted badly once usually reacts worse next time, so log the date, the number of stings and the minutes to swelling.
The same balcony carries ticks and hot paving. The pavement paw burn test takes 7 seconds: a palm held on the surface for 7 seconds tells you whether it is over 50 C. Tick checks fit into the same weekly pass, with season detail in the tick season guide.
Balcony Kit and Monthly Check
- One stiff card in the entry drawer for scraping a stinger.
- One gel pack at 4-8 C in the fridge, not the freezer.
- Two thin towels, one for the pack, one for drying.
- Soft tape and a phone folder for 3 photos per sting.
- A cone that fits, test-worn for 5 minutes.
- Clinic and 24-hour hospital numbers saved as favourites.
- Flashlight by the balcony door for the weekly check.
- Pest-control number, used for any nest over 5 cm.
Restock the kit on the 1st of each month from May to September, and re-check the 3 points after any storm, since a nest that survived 40 km/h wind is usually rebuilt within 72 hours.
When It Is Not a Sting
A swollen paw with no sting site, a front leg not bearing weight for 6 hours, or swelling still growing at 24 hours is a different problem: foreign body, claw-bed infection or bite abscess. If the cat was near balcony plants, open the household toxin list too, because oleander and some pesticides cause drooling and wobbling that looks like a sting.
Terms mentioned in this article
Frequently asked
Where do wasps build nests on a balcony, and how often should I check?
Check three spots once a week from June 1 to September 30: the underside of the railing within 30 cm of a corner, the ceiling corner above the balcony door, and ground level around planter drains, air-conditioning gaps and awning folds. Go out before 08:00 or after 20:00 with a flashlight, stand 2 m back and look up first. A nest the size of a 3 cm paper ball in June can reach 20 cm by September.
How do I tell a mild paw sting from one that needs the vet?
Measure the widest part of the paw at 0, 10 and 60 minutes and photograph it with the tape in frame. A front paw is normally about 3.5-4.5 cm; swelling to 6 cm within 10 minutes, or a cat that will not bear weight after 6 hours, needs a same-day exam. Mild cases get 10 minutes of cold, 10 minutes off, 3 cycles in the first hour, then twice a day for 24-48 hours.
What are the signs of a throat sting in a cat?
Drooling, a hoarse or changed mew, noisy breathing, 40 or more breaths per minute at rest, pale or blue gums, or pawing at the mouth. Swelling around the muzzle can close a nostril in 10-15 minutes, and anaphylaxis usually develops within 5-30 minutes. Leave for the clinic immediately and call on the way, and do not give a human antihistamine.