General Description: Megesterol is a synthetic progesterone used in dogs to treat false pregnancies and post-pone heat cycles. It may be used in cats to treat various behavior problems (ex. inter-male aggression, inappropriate urination, aggression towards people). It is also used to treat some skin conditions. Not for use in pregnant animals. Megesterol is available in two strengths: 5 mg and 20 mg tablets.

What is this drug?

A synthetic chemical similar to the female hormone progesterone
Given by mouth
Reasons for prescribing:

To post-pone estrus (female’s heat cycle) and alleviate false pregnancies in dogs
To treat some skin conditions (ex. endocrine alopecia, psychogenic alopecia)
To treat various behavior problems (ex. inter-male aggression, inappropriate urination, aggression towards people)
What dogs/cats should not take this medication?

Not for use in pregnant animals, those with reproductive disease, diabetes or mammary cancer
Should not be used in dogs prior to or during their first heat cycle
If your pet has had an allergic reaction to megesterol or like products

Read and follow the label carefully.

May be given whole, or crushed and mixed with food.

Ensure your pet has fresh, clean drinking water at all times.

Give the exact amount prescribed and only as often as directed. It is usually givenonce a day .

Give this medication for as long as veterinarian directs. Do not skip doses or stop giving the medication without consulting your veterinarian.

Ideally, give the medication at the same time(s) daily.

Periodic blood work to monitor this drug’s effect may be required if your pet is undergoing long- term therapy.

What if a dose is missed?

If a dose is missed, give it as soon as you can. If it is time already for the next dose, skip the missed dose and go back to the normal schedule. Do not give two doses at the same time.

What to tell/ask veterinarian before giving medication?

Talk to your veterinarian about:

When will your pet need to be rechecked
What tests may need to be performed prior to and during treatment with this drug
What are the risks and benefits of using this drug
Tell your veterinarian about:

If your pet has experienced side-effects on other drugs/products
If your pet has a history of blood clots, Addison’s disease or congestive heart failure
If your pet has experienced liver or kidney disease now or ever
If your pet has experienced any other medical problems or allergies now or ever
All medicines and supplements that you are giving your pet or plan to give your pet, including those you can get without a prescription. Your veterinarian may want to check that all of your pet’s medicines can be given together.
If your pet is pregnant or nursing or if you plan to breed your pet
Storage and Warnings:

Store in a tight, light resistant, childproof container in a cool, dry place at room temperature away from heat and direct sunlight.

Keep this and all medication out of reach of children and pets. Not for human use.

Call your physician immediately if you accidentally take this product.

Megesterol should not be given for more than two consecutive treatments.

Potential side effects:

Excessive thirst, excessive urination, personality changes, drowsiness, vaginal discharge, yellow gums and weight gain
Hair color change (dogs)
Contact your veterinarian if mammary changes (mammary enlargement, milk production) occur, or if any other side effects are noted
Can this drug be given with other drugs?

Yes, but possible interactions may occur with insulin and rifampin
If your pet experiences any unusual reactions when taking multiple medications, contact your veterinarian.

Contact your veterinarian immediately if pet receives more than the prescribed amount.

What else should I know?

Notify your veterinarian if your animal’s condition does not improve or worsens despite this treatment.

As with all prescribed medicines, megesterol should only be given to the pet for which it was prescribed. It should be given only for the condition for which it was prescribed.

This is just a summary of information about megesterol. If you have any questions or concerns about megesterol or the condition it was prescribed for, contact your veterinarian.

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