Human medicines and pets

All homes contain medicine which may have been prescribed by a doctor or bought over the counter, and some of these are toxic to pets. Many drugs cause similar signs in both pets and humans in overdose but in some cases pets are at particular risk because of their small body size or differences in metabolism. Some drugs can cause mild, short-lived toxic effects but others can cause severe poisoning that may require several days, or occasionally even weeks, of treatment.

©Douglas McCallum

Most human drugs are toxic in overdose. Those that have been reported to cause problems in pets include:

• Pain killers, particularly paracetamol, ibuprofen, naproxen, diclofenac and mefenamic acid, and opioid patches containing fentanyl or buprenorphine
• Cold, cough and flu medicines as these can contain pain killers, decongestants, cough suppressants, caffeine and antihistamines
• Heart medicines such as calcium channel blockers (eg verapamil, diltiazem) or beta-blockers (eg propranolol, atenolol)
• Caffeine supplements
• Antidepressants such as tricyclic antidepressants (eg amitriptyline, prothiaden), SSRIs (eg sertraline, fluoxetine), venlafaxine
• 5-Hydroxytryptophan (5-HTP) supplements
• AHDH medicines such as methylphenidate, lisdexamfetamine or dexamfetamine
• Asthma inhalers containing salbutamol, formoterol, salmeterol or terbutaline
• Psoriasis creams containing calcipotriol, calcitriol or tacalcitol
• 5-Fluorouracil cream
• Vitamin D supplements
• Any medicine, such as chewable tablets or oral sprays, containing xylitol.

If you discover your pet in the act of eating your medication you should immediately remove the medication from them. If you can do so safely, remove any suspect material from your pet’s mouth. Immediately contact your veterinarian for advice and be prepared to take your pet and the suspect material to the veterinary surgery. If it is possible, collect a sample of what has been chewed/eaten or a sample of vomit to take to your veterinarian. Make sure you take the packaging with you so your veterinarian can see what your pet has eaten. If possible, determine how much of the medicine is missing.

Do not attempt to make your pet vomit. Some medicines can cause effects very quickly including drowsiness and convulsions. If your pet vomits when they are not fully conscious they may not be able to swallow properly which could lead to choking and vomit entering the lungs. NEVER give salt water to make your pet sick, as this can cause salt poisoning.

Your veterinarian will want to know:

• What your pet has chewed, eaten or inhaled.
• How long ago the incident happened.
• If your pet is showing any signs of being unwell.
• If your pet is receiving any medication or has any pre-existing medical conditions.

When you arrive at the veterinary surgery someone will assess your pet immediately and make sure that its condition is stable before any other treatments are started. Your veterinarian may take some blood and/urine for testing to see if there has been any damage caused by the poison. In some cases it may be possible to measure levels of some toxins in the blood or urine. If you have been able to take the remaining medicine to your veterinarian they can measure the remaining drug to determine how much your pet may have taken. This information can help to guide treatment and will tell your veterinarian what signs they should expect. Your veterinarian may seek specialist advice from a poisons center to assess the risk, potential clinical effects and duration of poisoning.

Depending on what medicine is involved, how much has been taken, the time since exposure and the clinical condition of your pet, your veterinarian may give drugs to make your pet vomit and/or administer activated charcoal which can absorb some poisons. Further treatment will depend on what has been taken, the dose and the clinical condition of your pet. This may involve a short period of observation or hospitalization for monitoring and treatment. Antidotes may be given but unfortunately these are only available for a very few poisons. If appropriate, your pet may be transferred to an out of hours surgery or referral hospital for further treatment.

Pets usually recover from poisoning with human medicines, but this will depend on the drug and amount involved, the time between access to poison and treatment, and whether your pet has any pre-existing health conditions that exacerbate the toxic risk (such as renal failure or heart disease).

• Never give your pet a human medicine unless directed to do so by your veterinarian.
• Read the label of any medicine before use and only use as directed by your veterinarian.
• Store medicines securely, out of sight and out of reach of pets.
  • Do not leave bags containing medicines in the reach of your pet.
  • When removing your medicine from the container prior to taking, do not leave it unattended.
  • Replace the tops of containers securely after use. Clean up spills promptly.
• If your medicine is received in the post, use a cage on your letter box to prevent your pet accessing deliveries.
• Do not let you pet lick your skin after application of a medicinal cream or ointment.

It is essential that you seek advice immediately you suspect your pet may have ingested a human medicine. This will either ensure prompt treatment or give you the reassurance that the amount and/or drug ingested is unlikely to be a risk to your pet. Do not wait for your pet to become unwell before seeking advice.