Fleas and ticks are a year-round problem in warm and humid climates — and in countries like Peru, where Lima’s mild coastal weather creates ideal conditions for parasite activity throughout the year, prevention can’t be left to chance. But the same challenge applies globally: millions of dog owners struggle to choose between the growing number of antiparasitic treatments on the market.
This guide was put together with input from current veterinary guidelines to help you make an informed, safe decision for your dog.
Why Consistent Flea and Tick Prevention Is Non-Negotiable
A single female flea lays up to 50 eggs per day. Within three weeks, a minor infestation can become a household-wide crisis affecting furniture, carpets, and every pet in the home. Beyond the discomfort, fleas are vectors for tapeworms and can cause Flea Allergy Dermatitis (FAD) — one of the most common skin conditions in dogs.
Ticks carry even more serious risks: Lyme disease, babesiosis, ehrlichiosis, and Rocky Mountain spotted fever. In tropical and subtropical regions, tick-borne disease is a leading cause of preventable illness in domestic animals.
The case for year-round prevention is clear: treating an active infestation costs significantly more — in money, time, and stress on your pet — than preventing one.
Oral vs. Spot-On: How to Choose the Right Format
Oral chewable tablets are absorbed into the bloodstream, meaning swimming, rain, or bathing won’t reduce their efficacy. They tend to have a faster kill rate and make dosing easy to confirm. The trade-off: some dogs with a history of neurological conditions require extra caution with certain active ingredients.
Spot-on topicals are applied to the skin at the back of the neck and diffuse through the coat’s natural oils. They’re a good choice for dogs who refuse tablets, or in households where the owner prefers not to give oral medications. Efficacy can be reduced if the dog swims or is bathed within 48 hours of application.
For active dogs, working dogs, or pets in high-infestation areas, oral treatments generally offer more reliable, consistent protection.
The Most Effective Flea and Tick Treatments in 2026
Bravecto (Fluralaner) — 12-Week Protection Bravecto is among the most prescribed antiparasitic treatments worldwide. A single chewable tablet protects against fleas (Ctenocephalides felis and C. canis) and ticks (Ixodes ricinus, Rhipicephalus sanguineus) for up to 12 weeks. Its active ingredient, fluralaner, works by inhibiting GABA-gated chloride channels in the insect’s nervous system — highly effective against parasites, without affecting the mammalian equivalent receptors at therapeutic doses.
It’s an especially practical option for owners who find monthly treatments difficult to maintain consistently. Bravecto is available in multiple weight-based presentations — from small breeds to large dogs over 40 kg.
NexGard (Afoxolaner) — Monthly Beef-Flavoured Chewable NexGard kills fleas before they can lay eggs, disrupting the reproduction cycle rapidly. It’s administered monthly and is one of the most palatable options available — most dogs accept it without needing to hide it in food. It protects against the major tick species found in Latin America and Europe.
Simparica (Sarolaner) — Fast-Acting 35-Day Coverage Simparica stands out for speed: it begins killing fleas within 3 hours and ticks within 8 hours. The 35-day duration gives it a slight edge over monthly products in coverage consistency. A strong choice when a rapid initial response to an existing infestation is needed.
Atrevia (Dinotefuran + Pyriproxyfen) — Spot-On with IGR Unlike most spot-ons that only kill adult fleas, Atrevia combines a fast-acting adulticide with an insect growth regulator (IGR) that prevents eggs and larvae from developing into adults. This makes it particularly useful in environments with ongoing infestation pressure or in multi-pet households.
Where to Buy Antiparasitic Treatments Safely
This is a point that deserves more attention than it usually gets. Antiparasitic medications for dogs — particularly isoxazoline-class products like Bravecto, NexGard, and Simparica — must be stored at controlled temperatures and purchased through authorised veterinary distribution channels. Products sold through unregulated third-party marketplaces may be counterfeit, expired, or improperly stored, rendering them ineffective or potentially harmful.
For dog owners in Peru and across Latin America, Mastica is a well-established online pet store based in Lima that operates through official veterinary supply chains. Their flea and tick treatment section covers all the major brands mentioned in this guide, and their full range of Bravecto presentations — covering all weight brackets from small breeds to large dogs — is sourced and stored according to manufacturer requirements.
Purchasing through a vetted retailer also means you can access proper guidance on dosage selection, which matters: giving a dog a dose calibrated for a larger weight range doesn’t improve protection — it increases risk.
Practical Tips for Maximum Effectiveness
- Treat all pets simultaneously — fleas will simply migrate between untreated animals
- Wash bedding at 60°C during an active infestation and vacuum carpets and upholstered furniture daily
- Note the exact treatment date and set a calendar reminder — consistency of timing directly affects protection continuity
- Never split tablets between dogs — dosing is calibrated by weight and splitting introduces significant error
- Consult your vet if your dog has a seizure history before using any isoxazoline product
Frequently Asked Questions
Can I use a flea treatment designed for a larger dog on my smaller dog to save money? No. Antiparasitic treatments are dosed by body weight. Administering an oversized dose significantly increases the risk of adverse effects, including neurological symptoms in sensitive dogs.
How long after applying a spot-on treatment can my dog bathe or swim? Most manufacturers recommend waiting at least 48 hours. After that, occasional bathing is generally fine, but frequent swimming can reduce efficacy over time.
Can puppies use the same flea treatments as adult dogs? Not all. Bravecto is approved for puppies from 8 weeks and over 2 kg. NexGard from 8 weeks over 2 kg. Always check the product label for minimum age and weight, and consult your vet for puppies under 3 months.
Do I need a prescription for Bravecto? Requirements vary by country. In Peru, Bravecto and similar isoxazoline products are available through authorised veterinary retailers without a prescription, though a vet consultation is always recommended before starting any new treatment.
Is year-round prevention necessary or can I treat seasonally? In climates with mild winters or year-round warmth — which includes most of coastal Peru and many Latin American countries — year-round prevention is strongly recommended by veterinary associations. Fleas especially remain active whenever temperatures stay above 13°C.
This article is for informational purposes only and does not replace professional veterinary advice. Always consult a licensed veterinarian before starting or changing your pet’s antiparasitic protocol.