Fearless Flea Control

When your dog has fleas, all you want is for your dog to feel better and find the very best flea control. And you certainly don’t want fleas invading your home. Flea control is a two-part process: kill the live, biting fleas on your dog and kill the flea eggs, larvae, and pupae in your home. For flea treatment in your home, see my article Out Damned Fleas! Ridding Your Home of Fleas.

With any treatment, whether chemical or natural, please read and follow all directions. You want your dog to feel better not get sick from overexposure from chemicals. Just because a flea control says it’s “natural” doesn’t mean that you can ignore the directions. Some natural ingredients are just as dangerous as chemicals. For more information, read my article Are Flea Control Treatments Safe? Please consult with your dog’s veterinarian before starting any flea control treatments or changing medications. Use this article to become a better-informed dog owner.

Topical Treatments:

K-9 Advantix for flea controlTopical flea control treatments such as Advantix and Frontline have gained a loyal following over the last 5-10 years. Prior to their introduction, dog owners either had to use flea collars which were often ineffective, flea sprays which could rub off on hands or furniture, or flea powders which were messy. Topical treatments finally gave (most) dog owners an effective, neat method of flea and tick control and are often the first line of defense for flea prevention. Once a month, you apply a small amount of liquid to the dog’s neck between his shoulders. While formulas vary, essentially the liquid is a pesticide which kills fleas and ticks.

Topical treatments have two primary purposes: killing adult fleas and interrupting flea reproduction. The two most popular brands are Advantix and Frontline. Both treatments have their advocates. Both treatments have different formulations based on the weight of the dog. Both treatments have variations of their formulas available.

K-9 Advantix/K-9 Advantix II/Advantage/Advantage II:

These flea control products are all made by Bayer and seem to be variations on the same recipe. Both Advantix II and Advantage II contain an Insect Growth Regulator (IGR) which helps break the life-cycle of fleas. All products warn against use in young puppies (must be at least 8 weeks old), nursing or pregnant dogs, or dogs with any debilitating health issues caused by age, disease, or sensitivities. Out of the four formulas, the Advantix II seems to be the broadest preventative – but should not be used in homes where there are cats.

Advantix/Advantix II: The active ingredients in both K-9 Advantix formulas are Imidacloprid (8.8%) and Permethrin (44%). Advantix II, the newer formulation, adds Pyriproxyfen IGR (Insect Growth Regulator) (0.44%). This product family states that it prevents and treats for fleas, ticks, and mosquitoes. Caution: This formula can be TOXIC to cats. Consider using another product if you have cats in your home.

frontline plus for flea controlAdvantage/Advantage II: The active ingredient in Advantage/Advantage II are Imidacloprid (9.1%). Advantage II uses a slightly different formulation of Imidacloprid and adds Pyriproxyfen IGR, same as the Advantix formulation. Bayer advertises that this product kills fleas on contact and that fleas do not have to bite your dog to be killed. Product does not kill or repel ticks which can be a major drawback in areas where tick infestations are a real health hazard. Also does not kill or repel mosquitoes.

Frontline/Frontline Top Spot/Frontline Plus/Frontline Combo/Certifect:

These flea control products are all made by Merial, the same company that makes Heartgard heartworm preventer. Out of the five formulas, Frontline Plus seems to be the best reviewed and has fewer health problems. It runs about $60-$65 for a six-month supply.

Frontline Plus/Frontline Combo: These are the same formulations. Frontline Plus is the American version and Frontline Combo is sold in Europe. The active ingredients are Fipronal (9.8%) and (S) Methoprene (8.8%) an IGR (Insect Growth Regulator). Merial states that fleas are killed within 24 hours of application and ticks are killed within 48 hours. There are different formulas of Frontline for dogs and cats and they CANNOT be used on the other species.

Frontline/Frontline Top Spot: These formulas uses Fipronil (9.7%) to kill fleas but do not contain any IGR. Merial states that it kills fleas and several species of ticks (including deer ticks – the major carrier of Lyme disease). There are different formulas of Frontline for dogs and cats and they CANNOT be used on the other species.

Certifect: Interestingly, Merial does not advertise this flea control product on their website. Certifect seems to be their newest product, probably to get back some of the business lost to generic Frontline versions made by other manufacturers. It contains the same active ingredients as Frontline Plus – Fipronal (9.8%) and (S) Methoprene (8.8%) – but also adds a “Side B” which contains Amitraz (22.1%). This two-part product comes in dual-chamber vial which is applied the same way as other topical treatments. Amitraz is a repellent, particularly effective on Demodex Canis mites (which can cause mange) and ticks. It claims to be the only topical treatment that causes ticks to detach from your dog. Caution: CANNOT be used on cats. Not recommended for dogs with diabetes, heart problems, or other health issues. Online reviews of Certifect have been mixed; some people report their dogs having severe health reactions and others reporting that it simply does not work as well as Frontline.

Generic/Other Brand Versions of Frontline

Fiproguard for dogs for flea controlThe active ingredient in Frontline (Fipronil) has gone off-patent, so there are generic versions of Frontline that have become available (Fiprogaurd, Sentry FiproguardMAX, and Pet Armor are popular brands). They have the nearly same amounts of Fipronil ( 9.7% for Fiproguard, Sentry, and Pet Armor and 9.8% for Frontline) and dosage levels as Frontline. They vary in the other ingredients that make up the 90%+. Mostly they contain some type of alcohol solvent such as diethylene glycol monoethyl ether which can cause skin dryness. Sentry also includes 5.2% Cyphenothrin which is a member of the pyrethrin family. These non-Frontline brand flea control products tend to be roughly the same price ($55-$ 65) or a little cheaper than Frontline Plus ($65) for a six-month supply. Since the savings aren’t huge, I would stick with Frontline Plus; they have a long track record for safety.

Topical Treatment Cautions

There are online sites selling “bulk” topical flea control treatments which claim to have the same ingredients as the name brands. Often, you are sold a small bottle and a syringe for measuring out the chemical. I don’t know about you, but I have no way of know that what is in that bottle, that the concentration is as advertised, nor do I have any way of knowing if the dosage that they are suggesting is correct. While some users rave about the savings, all that could be wiped out in a single visit to a veterinarian because your dog suddenly becomes ill after this bargain flea treatment. I won’t take that chance.

Likewise, there are sites that advise you to buy off-the-shelf pesticides (“They contain the same ingredients! Save money!”). Don’t do this. Horrible idea to turn your dog into a science experiment. Maybe you will save money, or maybe you’ll be the one rushing your dog to the vet. Just say no to this crazy idea.

Sargeants Gold Squeeze-On flea control formula is reported to have caused many health problems with pets. Sargeant’s no longer seems to list it for sale on their website, although it is still available through various online retailers. According to the Sargeant’s site, the active ingredients in the Gold product are gokliat and nylar, but a little further research found that these are marketing names for Cyphenothrin (gokliat) which is a synthetic pyrethroid and Pyriproxyfen (nylar) which is an insect growth regulator (IGR). These are different than the Fipronil-based products. Based on many problems reported and customer’s general unhappiness with its effectiveness, I would avoid using this. As Sargeant’s seems to have stopped promoting it, that should be a red flag, too.

If you have cats in your home, you will need to be cautious about using K-9 Advantix/Advantix II. Both can cause health issues in cats if they come in contact with it for the first 48 hours after application. You may want to choose Frontline instead.

Topical flea control treatments take time to absorb into your dog’s skin. Your dog cannot get wet (no bathing or swimming for example) for 24-48 hours after application. If they get wet, the product may lose its ability to repel ticks, fleas, and mosquitoes.

Family giving dog a bath with flea shampooShampoos and Dips:

Shampoos and dips work by not only killing the fleas but also washing away flea droppings and saliva which are often the cause of irritation and inflammation.

Chemical-based flea control shampoos have proprietary blends of pesticides (including pyrethroids and pyridines) used to kill ticks and fleas. Some also contain an IGR such as (S) Methoprene to help break the cycle of fleas. Generally, you lather the dog up, wait a few minutes for the lather to work on the fleas and ticks, and then rinse. Some people use these in place of topical treatments. Most shampoos recommend usage no more than once a week and some no more than every two weeks.

Dips generally use a pyrethrin formula and are often applied after shampooing. The dip is sponged or poured over the dog and allowed to soak in. The dog is then air dried without rinsing, leaving the chemical to dry on the skin and fur. Think of a flea dip like a all-over treatment to get anything the shampooing might have missed. Like chemical-based flea shampoos, you need to read and follow directions. Most can’t be used more often than once a month. Same cautions apply: if you are using another chemical flea and tick treatment, you need to be very careful about not poisoning your dog as you battle the fleas.

There are also “natural” flea control shampoos and dips that rely on essential oils such as calendula, cinnamon, cloves, lavender, or mints. These can be used alone or with topical treatments. Some shampoos also contain oatmeal formulas to help soothe skin.

Do they work? Many people swear by them. Ovitrol, Zodiac, and Adams seem to have loyal followings and good online reviews for pesticide-based shampoos. Want to try a pesticide-free product? Bark Logic, EQyss, Kalaya Emu Oil, and Earthbath all have popular followings and passionate reviewers. Often, the pesticide-free products rely on essential oils such as lemongrass or citrus. Your dog smells good and looks clean. Often, they also contain skin-soothing ingredients to ease the itchiness of bug bites.

Overall, I make a good dog bath part of my anti-flea treatment. My dog gets a topical treatment, so I am careful to select a shampoo that does not have added pesticides or “natural flea killers” such as pyrethrins. Read below about MY secret weapon for dog bathing…


  • Great overall treatment which kills fleas and removes flea saliva and droppings which can go a long way to making your dog more comfortable.
  • Can be cheaper than topical treatments. Most bottles cost less than $10 and will do several shampoo treatments.
  • Your dog stays clean and fresh.
  • The act of lathering a dog with most any shampoo and leaving it on for five-plus minutes will kill fleas.


  • Short acting.
  • Some dogs are allergic to the active ingredients or essential oils and may actually end up with skin that is more inflamed.
  • Many of these flea control shampoos CANNOT be used for cats as the pesticides are toxic to cats.
  • Most pesticide-based shampoos should not be used on puppies younger than 6 months
  • You need to use the product (and bathe the dog) once a week.
  • You should not layer this over a topical treatment – one set of pesticides on your dog’s skin is enough.
  • Ticks are tougher to kill with any shampoo treatment.

Chemical Flea/Tick Collars:

These were the standards for many years for flea control. Flea collars generally work by depositing a chemical on the dog’s neck to kill the fleas. Most of these collars are better at killing adult fleas than flea eggs. Some collars just work to prevent ticks and leave you to deal with the fleas by other methods.

Today, collars such as Seresto use the same type of treatment found in topical treatments (such as Advantage) and put it in a flea collar. The theory is that the collar slowly releases a constant stream of chemicals to fight fleas. Preventic works on ticks only and uses Amitraz (same ingredient from Certifect topical treatment). Most users report using this in conjunction with another flea and tick controller such as a topical treatment.

Active Ingredients:

  • Amitriz is the active ingredient in Preventic. Note that this collar is for tick protection only.
  • Tetrachlorvinphos is the active ingredient in Hartz collars.
  • Propoxur is the active ingredient in Zodiac, Adams, Sentry collars.
  • Deltamethrin, a synthetic pyrethroid, is the active ingredient in Scalibor collars.


  • Traditional flea collars are generally less expensive than spot-controllers. Lasts 3-6 months.
  • Some people swear by them citing their low cost and effectiveness.


  • Some people swear at them citing the collars as completely useless.
  • Unless the collar is fairly tight against the dog’s skin, it is generally less effective than overall topical treatments.
  • Chemical remains around the dog’s neck and can transfer to hands or furniture.
  • Dogs with long or thick fur may not be able to get the full effect of treatment.
  • Takes a couple of weeks (at least) before the chemical really has a chance to absorb.
  • Seresto is nearly the same cost as topical treatments and does not have the same track record of effectiveness.
  • Preventic should not be used on dogs with diabetes or heart problems.
  • There is a danger of chemical exposure to children and the general environment. Propoxur, the active ingredient in Zodiac, Adams, Sentry Pro collars, is toxic to bees and birds. Chronic exposure in children can also be toxic.
  • Both Propoxur and Tetrachlorvinphos have been labeled a “likely carcinogen” by the Natural Resources Defense Council.

Natural/Essential Oil Flea Collar:

There are several flea control collars available which rely on citrus, orange, lavender, cinnamon, cloves, cedar, and/or lemongrass. In theory, the smell of the essential oils repels the fleas. In practice, owners report very wide range of satisfaction. Most agree that if you can’t smell it, it’s not working. As dogs have a much more heightened sense of smell, I can’t imagine that most are happy to smell like a candle shop at Christmas.

Just because it says “natural” does not mean that it is risk-free. Some natural pest collars contain pennyroyal and/or rue which can be toxic for dog’s livers and kidneys.


  • You avoid chemical application to your dog and your environment.
  • Your dog (may) smell nice.


  • May not be very effective.
  • Will not prevent ticks.
  • Some contain active ingredients which are just as toxic as chemicals.


Flea control sprays range from natural oils to full-on chemical controls. Sprays are applied all over the dogs and can provide immediate flea control, killing both fleas and their eggs. Some sprays are meant to be applied to rugs and furniture instead of your dog. I talk about home flea control in my article Out Damned Flea! Ridding Your Home of Fleas.

Chemical flea sprays often contain some form of natural or synthetic pyrethrin for flea control and an insect growth regulator (IGR) such as (S) Methoprene.

Natural flea sprays generally rely on essential oils such as peppermint, cedar, clove, lemongrass and other highly-scented oils. PETA includes a recipe on their website to make a “natural flea repellent by adding six or seven drops of the essential oils of rosemary, peppermint, eucalyptus, tea tree, and citronella to a cup of water and shaking well. Use a spray bottle to apply the solution to your dog’s coat every other day. (Do not use this on cats?they are too sensitive to essential oils.)” No reviews on this, but it follows the general “recipe” of many commercial natural flea repellents.


  • Faster-acting than topical or environmental treatments.


  • Must be reapplied often.
  • May or may not kill flea eggs.
  • Many people do not want to apply chemicals to their dog which could rub off on furniture and rugs in their homes.
  • If you are using other flea and tick treatments such as topicals, powders, or flea and tick shampoos, you could be dosing your dog with lots more active chemicals that you think.

Flea Combs:

Simply combing your dog with a fine-tooth comb is an effective (if tedious) method of flea control. The process is to comb, pick the fleas off the comb, and drop them in a bowl of sudsy water to kill the fleas. No chemicals. No treatments. Dead fleas. At least all the ones you find. Surprisingly, fleas don’t patiently wait in one spot for you to find them – it is literally hit and miss. And your dog may not be patient while you comb through fur, especially if their fur is thick or hard to comb.


  • You closely examine your dog and can track your progress.
  • No allergic reactions from chemicals or oils.


  • Slow.
  • Eggs are usually too small for the combs to get.
  • Dogs with thick or shaggy coats are difficult to comb effectively.
  • You should comb outside so fleas don’t re-infest your living areas as you remove them.
  • You will probably miss some (maybe a lot) of fleas.

Electronic Flea Control:

Electronic flea control comes in a few flavors. There are collar dangles, zapper combs, house plugins and more. There are various ways they are supposed to work. One product, Shoo!TAG supposedly sets up an energy field by harnessing your dog’s natural energy to power a magnetic strip and generate a frequency that repels pests. Users report wildly mixed results with some calling it worthless and others swearing that it is a godsend. Personally, I think it is junk science and wouldn’t waste my $30.

Electronic flea combs are supposed to electrocute fleas on contact. While they (sometimes) do that, users report that they are prone to clogging and may only temporarily stun the fleas. Most users still have to pick the fleas off and drop them in a dish of soapy water – exactly like a non-electronic flea comb. Verdict – they are no better than a traditional flea comb at killing fleas and are more expensive and prone to breakage. Other electronic devices claim to use ultrasonic sound to repel fleas. Extensive university studies (Purdue, University of California at Riverside, the University of Florida in Gainesville and Kansas State University) have proved that these devices are useless at repelling pests. The Federal Trade Commission (FTC) has taken action against several companies. Bottom line: they don’t work. Read this article in the Seattle Times

Pros: None.

Cons: Lots of money with no results.

Three boys and Golden Retriever dog

Homemade and Alternative Treatments: What Kills Fleas and What Wastes Your Money and Time

Vinegar: Some people have had success treating fleas with a vinegar-based spray. While proportions vary, most suggest 1 part vinegar to 1 or 2 parts water. This can be sprayed on your dog or used to clean areas which may be infested with fleas or flea eggs. Vinegar itself does not seem to kill fleas, but rather fleas don’t like the smell of the vinegar and will find another food source or place to hide. Of course, you have to want your dog to smell like a pickle factory all the time for this treatment to be effective. Once the smell goes away, there fleas can (and often do) return. And if your dog’s skin is irritated by flea bites or saliva, the acidity of the vinegar may be painful on inflamed skin. I could find no vet or medical articles which recommend vinegar for effective flea control.

Organic or Natural Oils: There are many variations on these mixtures. Some contain cedar oil, others highlight lemon or lemongrass oil. There are the clove and cinnamon sprays, and the rosemary crowd. Results are mixed (no pun intended). Some people swear by them, others swear at the waste of time and money. The common element seems to be some type of heavily scented oil which is supposed to repel fleas because they don’t like the smell. Most last just a few hours to a couple of days and then need to be reapplied to be effective. I could find no vet or medical articles which recommend natural oils for effective flea control.

The other problem with some of these essential oil sprays is they often contain linalool. Over 200 species of plants produce linalool, including mints, scented herbs, laurels, cinnamon, rosewood, citrus fruits, some fungi and others such as birch. It is commonly used as a scent. According to the U.S. National Institute of Health, oxidized linalool carries the risk of skin irritation and allergic reactions. Oxidation happens naturally as the essential oils are exposed to air – for example in a spray bottle. So the essential oil you are spraying on your dog to ward off fleas might be causing its own allergic reaction. Probably not what you intended.

My sister used a clove/cinnamon spray on her dog last summer when the sand fleas were particularly intense here on Cape Cod. She would apply this directly after bathing and Gracie would seem to have relief – for about a day. Coincidentally, the scent would be gone by this point too. As long as Gracie smelled like a candle shop at Christmas, she was scratching less – but even at its stinkiest, Gracie still was scratching. Considering that a dog’s sense of smell is so much keener than a human, I can only imagine what Gracie thought of the heavy cinnamon/clove scent – especially when you can’t get away from the smell. No wonder Gracie ran from the room whenever my sister pulled out that spray bottle.

Dawn Dish Soap (original blue): The Groomer’s Secret Weapon

Dawn blue dish soap

Dawn blue dish soap

While this is not homemade, it is a low-tech/very low-toxic solution for flea control. We stumbled on this recommendation when Gracie was infested with sand fleas. We put Gracie in the tub, wet a ring around her neck and lathered her up with a thick “suds collar.” We then washed her from the neck down. Fleas were literally dropping off her into the tub – nearly two dozen of the critters! By lathering a ring around her neck, they could not scamper up and into her ears or eyes or hide out under her neck where we would not be scrubbing and lathering as much. The barrier of thick lather kept them back. On advice from a groomer, we also paid particular attention to Gracie’s anal and genital region, making sure no fleas were hiding out.

What really surprised us was the dead fleas. Dawn killed them dead – working at least as well as any flea shampoo. Dawn left Gracie clean and the bonus was no toxic chemicals on her skin. While the fleas raged here in Cape Cod late last summer, this was by far the most effective relief for Gracie. We were bathing her a couple of times a week to get relief.

I have used this on Monty for the last few months with no ill effects. His coat is clean, his skin is clear, and (knock wood) no fleas. I was very concerned that the Dawn might dry out or irritate his skin, but that never happened. I was careful to rinse him VERY thoroughly – several minutes after the water started running clear – just to make sure that his skin had not traces of detergent.

More is NOT Better: Do not combine chemical (or natural) treatments.

CAUTION: It can be tempting to want to throw everything at your dog if he is suffering with fleas and your house is overrun. DO NOT turn your dog into a science experiment by combining different chemicals on your dog. You may cause more harm than good.

  • If you just applied a topical flea control treatment, stick to a non-medicated, non-flea killing shampoo. And make sure you wait the required period (generally 2-5 days) after applying topical treatments before you bathe your dog or allow it to swim. Getting the topical treatment wet will decrease (or eliminate) its effectiveness.
  • If your dog has been sprayed with chemical flea spray, don’t layer on a topical treatment until the dog has been bathed AND you are through the application period. For example, if it tells you not to apply more than once a week, wait a week, bathe the dog, and then apply the topical treatment.
  • If you spray outdoors for fleas, keep your dog away from that area until the label directions say it is safe for him to return.
  • Don’t use a topical flea control treatment and a flea collar.
  • Don’t be fooled into thinking you can use a natural treatment in combination with a chemical treatment. READ THE DIRECTIONS. Many “natural” flea treatments use plant-derived pyrethrins which act very similarly to chemical pyrethroids. You could be doubling the dosage on your dog.
  • Some flea control ingredients such as pyrethrin and pyrethrum (both derived from chrysanthemums) are natural and are relatively safe at low doses according to both the EPA and the National Pesticide Information Center (joint project of the University of Oregon and the EPA). Their biggest complaint is skin allergic reactions at the application site. But again, don’t use these along with the chemical pyrethroids found in many commercial flea treatments.
  • The active ingredient in permethrin is a synthetic formulation of pryrethrin/pyrethrum. Permethrin is toxic to cats and may cause hyperexcitability, depression, ataxia, vomiting, anorexia,tremors, or convulsions.
  • Online product reviewers seem to have a love/hate relationship with these products. Some dog owners report that one product failed after years of repelling fleas and ticks. Others report that their dogs never get any relief. Swear by it or swear at it, I would recommend getting the 3-month supply if you have never tried it on your dog. FOLLOW THE DIRECTIONS for best results. If one topical does not seem to work for your dog, try the other formula. They have different active ingredients and one may simply work better for your than the other.
  • Talk to your veterinarian. They will know which products are working for the dogs they care for. Buying from your veterinarian may be more expensive than online sources, but may give you peace of mind. That is priceless.

Try one flea control for a couple of weeks and then move on to the next treatment if it’s not working. Focus on treating the dog and eliminating fleas from the environment as two equal parts of the treatment process.

Note: This article is for informational purposes. Every dog is different and may have health requirements that require a veterinarian’s care. Please consult with your dog’s veterinarian before starting or changing any medications or treatments or starting any flea control methods.

Additional Resources:

Leave a Reply

Your email address will not be published. Required fields are marked *