Brief Answer:
Intraocular pressure has to be kept in control.

Detailed Answer:
Hello
Welcome to Health care magic

I am Dr. DADAPEER K, an Ophthalmologist and I answer health problems related to eye.

It seems from the history that you are diagnosed with glaucoma and you are on treatment with 9 pm eye drops. Glaucoma is characterized by raise of intraocular pressure and treatment is by reducing the intraocular pressure. The treatment options are use of anti glaucoma drugs, laser treatment or by glaucoma surgery.
9pm eye drops is latanoprost eye drops and as of now it is the first line of drug for treatment of glaucoma, hence do continue it as per the advice of your doctor.

Coming to your questions.
The involvement of one eye or two eyes in glaucoma depends on the type of glaucoma.
Primary glaucomas which usually occur in middle age and elderly individuals is usually bilateral and involve both the eyes but the involvement may not be symmetrical, it is common to see advance disease in one eye and mild in another eye.
However secondary glaucomas which follow injury, inflammation, congential anomalies.... are usually unilateral and will not affect the other eye.
Hence I advice you to confirm the diagnosis to predict the involvement of the other eye.

Coming to other question, regarding precautions to be taken,
The anti glaucoma eye drops should be used regularly as prescribed by the doctor.
Frequent examination at least once in a month to check the intraocular pressure is necessary.
Tests like visual fields should be done once or twice a year to assess the progression of glaucoma.

Since the glaucoma slowly causes loss of vision from the peripheral visual field, the damage may not be noticed till it comes to the centre, hence frequent eye examinations are very much essential and intraocualr pressure should be kept in normal level or at the target level to prevent progression of the disease.

Hope I have answered your question and the information is helpful to you.

Thank you
With regards

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