Bimatoprost (Ophthalmic)

By lowering high eye pressure, Bimatoprost helps to alleviate pain associated with com/health/coma/">glaucoma.

Overview

Bimatoprost is an ophthalmic solution that can be used to treat glaucoma and damage to the optic nerve. It is currently marked in the US and Europe by Allergan, under the name Lumigan. This medicine functions as a prostaglandin and reduces pressure by increasing the external flow of aqueous fluid from the eye.

In adults, ocular hypertension (high pressure in the eyes) often occurs as a symptom of general pulmonary hypertension. Bimatoprost can be used on its own to treat high eye pressure, or in conjunction with beta blockers, to alleviate general symptoms of high blood pressure.

Studies have shown that bimatoprost is comparatively one of the most effective treatments for ocular hypertension. Unlike other prostaglandins, it does not act on the F receptor, or any other prostaglandin receptor. Instead, it is thought to mimic the prostamides of the human body, which are similar in terms of chemical structure. It is, therefore, prescribed by doctors throughout the world as an efficient and affordable medication that is easily administered with relatively few complications.

Bimatoprost is relatively well absorbed via the cornea, is fact acting, and lasts for at least 24 hours. It can also be used cosmetically, as it has a propensity to accelerate the lengthening of eyelashes, along with helping to increase density and diameter. It has been approved for this purpose since 2008. Although the FDA approval in this context is for purely cosmetic purposes, the inability to sufficiently grow eyelashes is classed as a medical condition, known as hypotrichosis.

Conditions treated

  • Glaucoma
  • Ocular hypertension
  • Hypotrichosis

Type of medicine

  • Prostaglandin

Side effects

Along with the desired effects, Bimatoprost can also cause a number of unwanted side effects. The most common side effects experienced by patients undergoing treatment with these eye drops include blurred or decreased vision, bloodshot eyes, blindness, changes in color vision, changes in the skin around the eye, altered color perception, difficulty seeing in the dark/at night, double vision, dry eyes, changes to the color of the eye, seeing halos around lights, fever, chills, increased sensitivity to light, tunnel vision and redness and pain in the eyelid or inner lining of the eyelid.

Patients who experience any of the aforementioned side effects are advised to discuss this with their doctor or healthcare provider, who may consider altering the treatment or discontinuing the use of Bimatoprost altogether. However, the majority of symptoms that occur do so in a very minor way that causes only mild discomfort. In many instances, these side effects will not require medical attention, and are likely to lessen over time as the body adjusts to the medication. In most instances, the benefits of reducing pressure in the eye outweigh the risks of slight discomfort due do side effects.

During treatment with Bimatoprost, patients may also experience a number of side effects in areas of the body other than the eye. The most common of these include body aches and pains, difficulty breathing, headaches, ear congestion, voice loss, nasal congestion, sneezing, runny nose, sore throat, unusual weakness or tiredness. These side effects are also likely to dissipate as treatment continues.

Side effects which occur rarely (although frequently enough to warrant mentioning) include eye strain, a feeling of having something in the eye, and increase in hair growth and discharge from the eyes.

Because treatment with Bimatoprost can potentially affect vision, patients are advised against driving or operating heavy machinery while using this medication, in order to avoid putting themselves or others at unnecessary risk of injury.

Dosage

As with all medicines, it is incredibly important for patients to take Bimatoprost only as directed by a qualified physician. This means that patients should refrain from taking any more of the drug than advised - both in terms of frequency and dose size. In addition to this, patients should understand that, if a doctor recommends that they discontinue treatment, they should cease using Bimatoprost immediately, despite the fact that they may have a remaining supply of eye drops.

Adults and children suffering from intraocular hypertension should administer one drop in the affected eye(s) once every day, preferably in the evening. If the patient is using more than one ophthalmic medication at the same time, each of these medicines should be administered at least five minutes apart in order to avoid the mixing of medications. Patients can expect to experience a reduction in ocular pressure approximately four hours after the drops have been administered, with maximum efficacy occurring between 8 and 12 hours after using the medicine.

Adults and children suffering from glaucoma should administer only one drop in the affected eye once per day. The timeline of efficacy is the same as for those with intraocular hypertension, with effects being felt four hours after administration and a peak between 8 and 12 hours.

To administer Bimatoprost eye drops, patients should:

  • Wash hands prior to using the drops.
  • Tilt the head back, before pulling the lower lid of the affected eye downwards.
  • Hold the bottle of drops upside down, close to the eye. Patients should try to avoid touching the eye as they do this.
  • Apply enough pressure to the bottle in order to release a drop into the eye. Patients are advised to use no more than one drop. Increased dosage will not alleviate symptoms any further, but may increase the possibility of side effects.
  • Close the eye after administration of the drop, for a minute or two, while pressing gently on the side of the nose where the corner of the eye meets the nose. This will help to stop the drop from draining into the nose or throat and keep the solution in the eye.
  • Repeat the process in the other eye if the doctor has advised treatment in both eyes.
  • Replace the cap on the bottle and store it in a safe place.

When administering Bimatorprost, patients should take great care to avoid touching the dropper tip on any surface to avoid contamination. In the event of excess solution dripping onto the skin, patients should be instructed to clean the skin with warm or tepid water - this is because Bimatoprost can potentially cause darkening of skin it comes into contact with.

To lessen the potential for systemic absorption, patients should apply pressure to the tear duct immediately after they have administered Bimatoprost.

Patients are advised to avoid taking double doses. In the event that a patient misses a dose, they should take the missed dose as soon as possible, unless it is nearly time to take the following dose. In this instance, patients should administer the following dose as normal and continue with treatment as standard from thereon in.

Patients who experience symptoms of overdose (fast heartbeat, difficulty breathing, loss of co-ordination) should contact their local poison control center on 1800-222-1222 or visit their nearest emergency department immediately.

Interactions

All medications can potentially interact with other drugs or chemicals in the body. These interactions can potentially affect the way in which one or both medicines function, and can lead to medicines becoming ineffective. Sometimes, interactions can even result in potentially harmful side effects occurring.

For these reasons, it is imperative that patients keep a detailed list of all the medications they are currently taking. This includes over the counter medicines, such as cold and flu relief, herbal supplements, such as natural sleep aids, and multivitamin compounds. Patients should provide their doctor with this list so that any potentially harmful interactions can be recognised and ruled out prior to the administration of a treatment.

Below is a list of medications known to interact negatively with Bimatoprost. Patients who are currently undergoing treatment with any of these drugs should inform their doctor before taking the first dose of Bimatoprost:

  • Latanoprost
  • Xalatan
  • Latisse

Although there are few drugs known to interact negatively with Bimatoprost, it is possible that certain medications could potentially interact with the drug, despite there being no current data to suggest this is the case. In the event of a patient experiencing an interaction between Bimatoprost and another drug, they should inform their doctor and the FDA, detailing how the interaction occurred and which side effects were present.

No interaction studies regarding this medication have been performed, although interactions with systemic drugs are not considered likely on account of the fact that Bimatoprost does not reach particularly large concentrations in the bloodstream.

Patients are advised to also inform their doctor or healthcare provider if they are taking any substances in a recreational capacity that might affect their condition. This is because alcohol and other substances can affect blood pressure, which, in turn, can affect the level of intraocular pressure, rendering treatment with Bimatoprost ineffective or not as effective as it should be.

Warnings

In addition to providing a doctor with a list of current medications, patients should also discuss their medical history, including any current health conditions. In some instances, Bimatoprost dosage may need to be adjusted to account for other conditions.

Macular edema, including instances of cystoid macular edema, has been reported by patients undergoing treatment with prostaglandins, including Bimatoprost. The majority of these cases involved patients who were already suffering from a torn posterior lens capsule, aphakia, psuedoaphakia or other risk factors for macular edema, including posterior uveitis and retinal disorders. In patients with these conditions, treatment with Bimatoprost should be administered carefully, and monitored until it has been proven that no specific risk exists.

Because Bimatoprost is a synthetic prostaglandin analogue, in theory it may mimic endogenous prostaglandins and contribute to certain inflammatory responses in the eye, such as uveitis and iritis. Although these conditions have been reported rarely in patients undergoing treatment with Bimatoprost, caution should be taken when prescribing or administering this medication in patients who have intraocular inflammation.

Although there is scant evidence that Bimatoprost can have negatively affect patients with reported liver or kidney conditions, it is worth noting that the medication is systemically absorbed and subsequently metalbolized rapidly by the liver, before being eliminated by the kidney. Therefore, the potential to cause complications in patients with impaired renal or liver function exists. As such, treatment with Bimatoprost ophthalmic solution should be administered with caution in such patients.

During pregnancy, Bimatoprost should only be prescribed only if clearly needed. Pregnant patients should discuss the benefits and risks of using this medicine with their doctor before committing to treatment. This is because studies have shown that Bimatoprost can cause reproductive toxicity at exceptionally high doses, with evidence of an increased potential for fetal damage.

It is not currently known whether Bimatoprost is harmful if excreted into breast milk, so mothers who are currently breastfeeding are advised to consult with their healthcare provider for advice. In some instances, a doctor may advise women to avoid breastfeeding until the course of treatment with Bimatoprost has come to a conclusion. Although no human studies exist, animal studies have shown that the compound can, and invariably does, pass into breast milk.

Patients with allergies should disclose the nature of said allergic reactions to their doctor prior to treatment with Bimatoprost. This is because the medicine may contain inactive ingredients that can cause allergic reactions.

Before commencing treatment with Bimatoprost, the patient should be aware that potential changes in eye color can occur. This is because the medicine has a propensity to increase the brown pigment within the iris. This change in eye color can be permanent. Particular care should be taken in patients who have mixed-color irises, as well as those receiving treatment in one eye only, as this can mean one eye may end up with different coloration to the other.

Where possible, repeated contact of Bimatoprost solution with bare skin should be avoided, as it can stimulate hair growth and affect skin pigmentation.

Those with the following conditions should take great caution when commencing treatment with Bimatoprost:

  • Patients who are pregnant or breastfeeding
  • Patients who have undergone eye surgery to remove or replace the lens (for example, removal of cataracts)
  • Patients with breathing disorders, such as COPD or asthma
  • Patients who have previously had issues with ocular viral infections
  • Patients with kidney or liver issues, regardless of how minor or moderate
  • Patients who are using any other eye drops, including herbal and complimentary medicines that are available without a prescription

Storage

Bimatoprost should be stored in a cool and dry place, away from natural light and direct heat, and out of the sight and reach of children. Once a bottle of these drops has been opened, it can be used for a period of up to four weeks.

After four weeks, the solution should be discarded in a safe and hygenic manner, even if some of the solution remains. Replacing the bottle with a new one helps to prevent the risk of infection. Unwanted Bimatoprost solution should not be poured down the toilet or drain.

Summary

Bimatoprost is effective in the treatment of glaucoma and ocular hypertension, and, because it has relatively low potential to interact with other drugs or otherwise cause negative side effects, its use is widespread throughout the world in comparison to other prostaglandins. It functions by increasing the drainage of fluid from within the eye, which ultimately results in lower pressure.

In order to get the best possible results from this medicine, patient and doctor should work together in order to ascertain the right dosage and frequency of treatment.

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Last Reviewed:
December 25, 2017
Last Updated:
April 04, 2018
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