Is there a natural alternative to chemical wormers?

Vets CornerMost responsible dog owners will treat their pet for worms, but many are reluctant to use chemical products for fear of unpleasant side-effects. Paul Boland looks at the best way to prevent worms in your dog, as well as some natural remedies and herbal treatments that can be effective.

Animals can pick worms up in a number of ways. Common ways to get worms are from ingesting their larvae or eggs from infected faeces, urine or in grass. Many worms are also ingested from food, and fleas can  carry tapeworm eggs.

Because even healthy looking animals can carry worms many infected animals don’t show any outward signs. Some obvious signs that you can look out for are worms in the faeces or vomit or around your pets bottom. Other signs would be a sudden loss of weight, increased appetite, general weakness, bottom licking (more than usual) and fur becoming matted, dry or course. Severe cases can show itself in a distended abdomen. Not all worms are the same so if you do see anything that looks like a worm on or near your animal keep the worm by wrapping it in a piece of damp kitchen towel or cotton wool and take it to your vet for examination.

The standard veterinary approach to removing worms is by using pharmaceutical wormers, however these can have many side effects with the most common being diarrhoea and vomiting. I think dogs, like humans, get too many pharmaceuticals with conventional medical advice. Wormers are a good example of over-prescription within this group. I believe they are overused and employed against good medical practice.

Common pharmaceutical wormers

Most manufacturers of pharmaceutical wormers recommend worming every three months, but in some cases wormers are even given monthly. The most common worming products in veterinary medicine today are Drontal Plus (pyrantel and praziquantel), Milbemax (milbemycin oxide and praziquantel) and Panacur (fenbendazole).

Pyrantel acts on the worms nervous system as a nicotinic receptor agonist. It can elicit spastic muscle paralysis in parasitic worms due to prolonged activation of the excitatory nicotinic acetylcholine receptors on worm body wall muscle. It’s effects are mainly against round worms.

Surprisingly, considering how universally it is used, the mode of action of praziquantel is not exactly known. Effects on the permeability of the membranes of the parasite, paralysis, focal disintegration and disturbances of ovipositioning (egg laying) are all postulated. Praziquantel is active against tapeworms (the worms that look like tagliatelli or rice).

Milbemycin oxime is derived from fermentation of Streptomyces moulds similar to the avermectins, which are also derived from the Streptomyces mould family. It has a paralyzing and perhaps a lethal effect on round worms’ nervous system. Collies and other susceptible breeds have a lower toxicity threshold than most dogs.

Fenbendazole has been around for a long time. It binds tubulin causing paralysis of the worms. It’s a broad spectrum wormer, but has considerable resistance issues worldwide. Although it’s poorly absorbed from the gut, it is still known to have toxicity issues in some bird and reptile species.

Drontal Plus, Milbemax and Panacur are considered to have low toxicity in dogs, although I find that one sees idiosyncratic (individual) reactions with about 1 in 100 dogs who, for some reason, just cannot use one or other of these products. Resistance problems, apart from Fenbendazole, are not common at all.

Combating worms naturally

There is no way to completely stop your pet becoming infected by worms but I would approach this  in a simple four-step process:

1. Consider the environment your animal lives and spends time in.

2. Use an effective herbal product frequently for life, to promote optimal gut function from 4 weeks old.

3. Use Worm Egg Counts every 3 months to assess for worms and lungworm in the gut.

4. Use pharmaceuticals, but only if necessary.

Consider your pet’s environment

There is no point treating the worms only for the animal to go and immediately become re-infected. The first step is consider the environment your pet lives and spends time in.

Clean your pets food and water bowls regularly and make sure the bedding and housing is cleaned and refreshed regularly. Clean up after your pet as soon as possible and dispose of any faeces and urine carefully.

If you own horses, rabbits or ponies or your dog spends a lot of time outdoors in your garden it is worth keeping this area completely free of droppings and faeces. In the case of horses it is advisable to rotate the areas the horse visits and ensure good pasture management. This will help to prevent them from eating the larvae and eggs of the worms.

For rabbits in particular avoid collecting fresh greens from areas where wild rabbits and rodents may have been.

Finally for your own and your families benefit wash your hands regularly

Herbal alternatives to pharmaceutical wormers

There are many benefits to using natural worming products over pharmaceutical wormers.

– An holistic approach to the gut and parasite control makes much more sense than just killing the invaders alone. This is borne out in practice; if a dog is presented with masses of intestinal worms, using a conventional wormer can be dangerous if all the worms detach from the gut wall and die in the body all at once. Using a herbal product, the kill effect is more gradual and gentle, ideally over a number of weeks, and the carminatives and the vulnerary herbs are on hand to offer the gut first aid to help with healing where it’s needed.

– During our studies all vets are taught to worm bitches every month through pregnancy to reduce transmission of worms via milk to the pups. New evidence suggests that this does not work. The best way to reduce or prevent maternal transmission of worms (which always happens) is to give natural worming products in the first weeks and months of life.

– Young animals need some exposure to worms with an optimally functioning intestine and gut immune system. Killing off worms willy nilly by using pharmaceutical wormers in pups without enhancing and promoting future adult gut immunity is asking for trouble down the line.

I find that, generally, once a dog is mature, and has built up a resistance to worms naturally, they are clear of worms for years and years without any pharmaceutical worming at all. The exceptions to this are puppies, in-whelp and lactating bitches and debilitated animals.

Natural wormers work in an entirely different way to pharmaceutical wormers.  Herbal products can be used to optimise gut function, health and immunity, not just kill worms. Their effects promote the body’s defenses. Effective herbal products contain mixtures of herbs. Herbs are complex naturally sourced combinations of hundreds of plant biochemicals. Typically one herb will contain 4-600 different molecule types.

Different herbs are selected and blended for a given effect. Some herbs in the mix promote improved gut function (the carminatives such as fennel and mint), some are vermicidal and/or vermifugal (kill worms and/or paralyse worms respectively e.g. quassia and garlic), some are immune modulating, for example, garlic and Echinacea, some antimicrobial (e.g. thyme and cinnamon) and some have vulnerary effects (healing and anti-inflammatory e.g. nettle and slippery elm).

One other major benefit of natural wormers are they are a much more cost effective option than pharmaceutical wormers.

Worm Counting

At my practice I recommend that all animals have a stool worm egg count every three months to test for evidence of worms. This is a simple and cheap procedure involving collecting a walnut sized piece of faeces and sending it off, well wrapped, in the post, to . They analyze the sample and email you a result within a couple of days. They can also offer advice. Lungworm eggs can be tested for, too, using the Baermann test if you send them three samples from consecutive days.


Sometimes pharmaceuticals need to be used as a last resort and only in the short term. I would not suggest the long term continual use of pharmaceutical worming products.  Instead I’d suggest Verm-ex products, which are good for dealing with worms and are particularly effective when it comes to dogs and horses.


An holistic approach to worming and in particular using a herbal worming product would be better for your dog throughout its life. Helping to build your dogs own defenses to worms may help to keep your dog worm free for life rather than the continual use of pharmaceutical products which are only aimed at killing the worms and give no other benefit whilst also potentially having a number of side effects.