Preventing parasites in pets in the first place is the safest solution
The proverb "prevention is better than cure" originated in the early seventeenth century, but even before then, the idea was well known. There was a Latin saying in the mid 13th century which said 'it is better and more useful to meet a problem in time than to seek a remedy after the damage is done". The concept is a simple and universal truth.
It is well recognised that there's great value in owners preventing problems in their pets, rather than waiting until they fall ill and then trying to treat them. The two main areas of preventive medicine are firstly, prevention of infectious illnesses by vaccination, and second, prevention of parasites by regular dosing with medicines. I've discussed vaccines before, so this week, it's the turn of anti-parasite medications.
In most cases, it's safer and more efficient to give regular medications to your pets to prevent parasites: this can mean tablets, spot-on products, sprays or impregnated collars, and they may need to be repeated monthly, every two months or every three months, depending on the situation. Most vets are happy to advise pet owners about the best preventive approach for their pet, and this type of individualised advice is definitely the best answer.
All young animals - puppies and kittens - need to be given regular anti-worming medication, as they nearly always pick up worms from their mothers. Typical recommendations are a worm dose every two weeks up to three months of age, then once a month till six months. Parasites in adult pets are more complicated. The best approach for these is to work out what the risk is, and then to take appropriate action.
First, ticks. If your dog or cat picks up a tick only once or twice a year, rather than using a continual dose of anti-tick medication on your pet for such a low risk, it may be more appropriate to just keep an eye out for ticks, and to remove them using a tick-removal tool (such as the O'Tom Tick Remover).
On the other hand, if you live in an area where your pet comes back carrying multiple ticks every week, it definitely makes sense to use a tick control product, whether table, spot-on or collar. Modern medications of this type are safe and highly effective. Why expose your pet to a continual challenge with ticks if there is a simple answer?
Second, fleas. If your dog or cat spends most of their time indoors, and rarely meets other animals, then the risk of picking up fleas may be very low. In such cases, it may be acceptable to simply monitor them, and if they ever start to itch, or if you see evidence of fleas in their coat, only then do you need to go ahead with a potent flea treatment.
If you are going to take this approach, you should invest in a flea comb, using it to regularly check their coat for fleas, or for evidence of fleas (small black specks of dried blood in the coat that fleas leave behind them: it's known as "flea dirt".)
On the other hand, if your dog or cat spends time outdoors, regularly socialising with other pets, there's a high risk that they will pick up fleas, bringing them back into your home. And once fleas have arrived in your home, they will multiply, laying eggs in your carpets and soft furnishings. At this stage, it will be more difficult to get rid of them: as well as applying treatment to your pets directly, you will need to spray your house with a special environmental spray to kill the fleas and to prevent their eggs hatching out.
You can see why the idea of applying a simple monthly vial, a quick spray every two months, or a tablet every 1 - 3 months is so appealing. It's just easier and quicker to prevent major flea problems by using regular products like this.
Third, worms. Again, if your dog or cat is an indoor pet, rarely going out and about, not hunting at all, and not engaging with other animals, then the risk of a serious worm burden is very small. You should still pay attention to the small risk that your pet could carry worms that may affect humans, and for this reason, it still makes sense to give a routine worm dose every three months or so, using a product that kills roundworms. You can buy such products over the counter.
However, if your pet does spend time outdoors, there are other worms that you should pay attention to.
For cats, if they hunt small rodents and frogs, they are likely to pick up worms like tapeworms, and these can cause ill health. There's no point in waiting until they are unwell (tapeworms can cause weight loss, a dry staring coat, and general lack of vitality). Instead, it makes sense to give a once monthly medication (again, as a spot on or as a tablet), making sure that it covers roundworms and tapeworms.
For dogs that spend time outside, the biggest risk is lungworm, which can stop the blood from clotting, rarely causing sudden death from internal bleeding. Dogs pick this up by eating slugs or snails: they can this accidentally by chewing grass or licking dinner bowls outside. So if your dog has these types of habits, they should definitely be given a monthly product to treat lungworm, either as a spot-on or a tablet.
The best rule is simple: talk to your own vet about the risks to your pet. Different parasites thrive in different areas. Personalised, localised advice is the safest answer.