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Can I Give My Dog His Antibiotic 2 Hours Early?

If you are here, it’s come the time that your dog has been prescribed antibiotics. Depending on the medication, your vet will determine how long and how often they need to be taken. But how strict do you have to be on the timing? Can you give your dog his antibiotics 2 hours before the allocated time? Will it cause any harm? Well, here is everything you are going to need to know. 

So, can I give my dog his antibiotics 2 hours early? It’s best to stick to the administration schedule given to you by your vet. However, you may be able to give certain antibiotics 1-2 hours early if this is the only option, and you do not do this too regularly. It’s better to give antibiotics slightly early rather than late, as the latter can leave your dog in pain. 

For the most part, this is not something you want to get into a habit of.

There is a reason why antibiotics are prescribed within allotted times.

And as such, if you do decide to go ahead, you will need to observe and monitor your dog closely.

So with this in mind, let us continue to explore the possibilities, along with clarifying some other questions that you likely have. 

Can I Give Antibiotics To My Dog Early? 

As a general rule, it’s not recommended to give your dog antibiotics any earlier than stated by your vet. However, there is a bit of wiggle room because the majority of drugs have wide margins when it comes to safety. Most dogs will be fine if you need to administer their antibiotics 1-2 hours early, but this should only be done if you really need to.  

Antibiotics are usually prescribed based on your dog’s weight and the type of infection or illness that needs treatment.

For example, A typical dose of Amoxicillin used by the majority of vets is 5-10mg per pound.

So, a dog weighing 50lb will require around 500mg twice a day.  

However, issues can arise when dogs have other underlying health conditions or they are elderly.

These factors may reduce a dog’s ability to effectively metabolize these drugs, which can lead to complications if doses are given too close together.

Furthermore, your vet will want to determine if your dog has any history of allergic reactions to particular groups of antibiotics before prescribing/

Symptoms of an overdose will vary depending on the type of antibiotic prescribed. Here are a few examples: 

  • Amoxicillin – The main symptom of an amoxicillin overdose is nausea. However, drooling, diarrhea, excessive panting, and a loss of appetite can also occur. In extreme overdoses, dogs can suffer from a loss of coordination, inflammation, and kidney failure. An overdose is highly unlikely if you give your dog his meds slightly early, but it’s always better to be safe than sorry. 
  • Enrofloxacin – More commonly known as Baytril, this antibiotic is often used to treat skin and ear infections. Standard doses can make your dog feel a little lethargic. However, an overdose can cause weakness, vomiting, dizziness, depression, and even seizures. It’s worth mentioning that enrofloxacin should never be administered to pregnant, nursing, or very young dogs except in extreme circumstances. 
  • Sulfadimethoxine – On its own, this drug is almost exclusively administered to treat intestinal parasites known as Coccidia. However, it can be used in conjunction with other antibiotics to treat a broader range of illnesses and infections. One of the most common side effects of this antibiotic is the reduction of tear formation. So, an overdose can exacerbate this problem. Serious side effects include joint inflammation, skin rashes, and the formation of urine crystals.  
  • Tylosin – Dogs are generally known to be able to cope well with high doses of this antibiotic. However, an overdose can increase digoxin blood levels, which is a drug used to treat heart conditions in dogs. So, you need to be very careful about using this antibiotic in dogs that take digoxin for heart failure.  
  • Metronidazole – Again, side effects are generally not often seen with this medication. However, a severe overdose can cause neurological symptoms such as staggering, a head tilt, back-and-forth eye movements, and dilated pupils.  

The good news is that an overdose is very unlikely unless your dog gets into the medicine cabinet. However, it’s important to remember that vets prescribe a particular dose for a reason. So always try to stick to the guidelines given as much as possible. 

How Early Can You Give Your Dog Antibiotics? 

How early you can give your dog antibiotics will depend on the type of drug and how often it should be administered. For example, if an antibiotic is prescribed to be given once every 12 hours, then administering the next dose after 10 hours should be fine. However, if your dog should be taking an antibiotic every 6 hours, you shouldn’t administer it more than once every 5 hours. 

When you get home from the vet, it’s best to set out a schedule that you can stick to, so you don’t end up being halfway through your workday when the next dose should be administered.  

So, what happens if you miss a dose? The most important thing is to not double dose to make up for the one you missed.

This can cause some of the side effects we mentioned above.

For most drugs, you can simply wait until the next allotted time to give your dog a dose.

Alternatively, you can give your dog the missed dose immediately and then re-adjust your schedule for the next dose. 

For example, your dog was supposed to get a dose every 6 hours, but you missed his 3 pm dose.

If it’s 4 pm, you can probably just administer the missed dose and stick to the schedule for the next one.

However, if it’s more than 50% passed the time of the dose, which in this case would be anything past 6 pm, then you are better off just waiting to administer the next dose.

This 50% rule generally works well with most drugs.

However, if the antibiotics are treating a potentially deadly illness such as pneumonia, then you must stick to the schedule as accurately as possible.

If you think you may have accidentally given a dose too early or missed a dose, it’s best to seek advice from your vet. 

Is It Better To Give Dogs Antibiotics Early Or Late?

If you need to leave the house for a few hours and your dog is due his next dose when you’re out, then it’s better to give the antibiotic early as long as it doesn’t break the 50% timing rule. 

Leaving your dog for too long before the next dose will likely leave them in pain.

This issue becomes more prominent if your dog has a detrimental condition such as a respiratory infection or post-surgery pain. 

There are a few very generalized rules you need to stick to when administering antibiotics, which include:

Don’t Skip Doses Or The Full Course

Don’t repeatedly skip doses or fail to complete the whole course of antibiotics – Skipping doses can leave your dog feeling worse and may even lead to complications.

Even if your dog seems better, it’s essential to finish a whole course of antibiotics because symptoms can return if the internal infection is not completely cleared up.

Stopping a course of antibiotics halfway through because your dog seems fine may also lead to antibiotic resistance.

This allows the remaining bacteria to grow and multiply in your dog’s body.

The first few doses of antibiotics will kill the majority of bacteria, but there will always be some bacteria that will be more resilient.

By not finishing a course of antibiotics, you are allowing these stronger bacteria to thrive, which will be harder to treat because they will already have become resistant to certain antibiotic treatments.

For the same reason, it’s also important to only administer antibiotics to your dog when they really need them.  

Don’t Used Old Prescription Antibiotics

Don’t start using old prescription antibiotics that you have left over from the last course of treatment – If your dog starts to show similar or the same symptoms as the last time they were ill, it can be tempting to just start giving leftover tablets.

But this is not recommended.

Most drugs have a shelf life of around 6 months, but this will vary depending on the type.

By giving your dog out-of-date prescription medications, you could be causing more harm than good.

If symptoms return, it’s always best to speak to your vet, as they may recommend a different approach.  

Never Give Human Antibiotics To A Dog 

Many human drugs are incredibly toxic to dogs, so always stick to the antibiotics given to you by your vet.  

What Can Happen If You Give Your Dog His Antibiotic Early? 

If you give your dog his dose of antibiotics a little bit too early, then your dog should be fine. However, a double dose or an overdose can cause complications. Mild side effects include vomiting and diarrhea. But remember that these ailments can quickly turn into dehydration which is much more dangerous. A dog that has overdosed on a particular drug can suffer a wide range of effects, from seizures and other neurological symptoms to kidney or heart failure.  

For this reason, it’s important that you stick to the schedule given by your vet as much as possible.

Especially if your dog is on more than one type of medication or has multiple medical conditions, remember that some over-the-counter medications can react with certain antibiotics, so you need to exercise caution in these circumstances and speak to your vet if you are unsure.  

You should also make sure that you safely store medications in a locked cabinet so your dog can’t gain access to them.  

How Long Do Antibiotics Take To Kick In? 

Many antibiotics take 1-2 hours to kick in. However, this will vary somewhat between different types of drugs. In general terms, you should start to see a difference in your pet within 24 hours of starting a course of antibiotics.

Within 72 hours, you should see a significant improvement.

If you don’t see any improvement in your canine companions’ symptoms after 3 days, it’s best to speak to your vet because a different type of medication may be required. 

Bear in mind that some dogs are also allergic to certain groups of antibiotics. So, especially in the beginning, you need to watch for signs of an allergic reaction which can include: 

  • Hives 
  • Facial swelling 
  • Itchy skin 
  • Watery eyes or nose 
  • Lethargy 
  • Difficulty breathing – if you notice this symptom in your dog, you must get them to a vet immediately. This can be a sign of anaphylactic shock which can be fatal. 

Bear in mind that certain dog breeds are more prone to developing adverse reactions to antibiotics, particularly Collies, Australian Shepherds, and other related breeds.

This is believed to be caused by a gene mutation that allows these drugs to build up in the brain.

This can cause dangerous neurological symptoms such as seizures, tremors, disorientation, and blindness.

Speak to your vet to find the best solution to treat your dog’s health condition, depending on their age, breed, health status, and individual circumstances. 

Tips To Ensure You Give Your Dog His Antibiotics On Time 

Here are a few tips to help you make sure you can stick to your dog’s antibiotic schedule as much as possible:  

Consider Making Up A Medication Time Sheet

This can be as simple or as elaborate as you like.

The most important thing is to write down the specific times and days your dog will need medication.

Place this somewhere in your home where you will see it often, or set reminders on your phone.

Laying out this type of schedule will also help you to identify any times that may prove difficult due to other commitments.

By working this out early, you will have time to come up with an alternative plan to make sure your dog gets the medication they require at the allotted times. 

Ask A Friend Or Family Member To Help

If you know you are going to be out of the house when your dog is due a dose of antibiotics, ask a friend, neighbor, or family member to pop around and administer the antibiotics to your dog.

Just ensure your dog knows them well and the person knows exactly how to give the medication.

Inviting them around beforehand is a good idea because it gives you the opportunity to go through the specifics.  


If your dog has been prescribed antibiotics; it’s important you do your best to administer them on time.

But if you are really unable to stick to the schedule provided, try speaking to your vet.

Often, they will be able to discuss alternative solutions that will better fit your lifestyle.

It’s also essential that you read and understand the administration instructions for the drugs you have been prescribed before starting the course.

This way, you will be able to plan better, especially if the drug needs to be given with food.  

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