If you’ve got cataract surgery coming up, there’s a good chance you’re also taking medication for something else — maybe high blood pressure, diabetes, an enlarged prostate, or a heart condition. One of the most important conversations you’ll have with your surgical team before your procedure is about what’s in your medicine cabinet. That’s because some drugs can interfere with the safety, effectiveness, or recovery from cataract surgery. And while you should never stop anything without proper medical advice, it’s vital that your ophthalmologist and anaesthetist know exactly what you’re on — so they can make informed recommendations tailored to you.
Let’s walk through the major medication groups that might come up during your pre-operative check, what your surgeon may advise in each case, and how you can prepare for a smoother surgery.
1. Blood Thinners: Are They Safe to Continue?
Blood thinners are commonly prescribed to prevent stroke, heart attacks, or blood clots. These include aspirin, clopidogrel (Plavix), warfarin, apixaban (Eliquis), rivaroxaban (Xarelto), and others. The big worry with these drugs is the potential for bleeding. Although cataract surgery involves very small incisions and is typically performed under local anaesthetic, there’s still a risk — especially during injections around the eye or if any complications arise.
In most cases, your surgeon will evaluate your bleeding risk versus clotting risk in collaboration with your GP or cardiologist. Some patients can safely continue their anticoagulants, especially if they’re undergoing clear corneal phacoemulsification without peribulbar injections. Others may be advised to pause or adjust timing. For example, warfarin may be temporarily withheld if your INR is too high, while newer oral anticoagulants are sometimes held the morning of surgery. Always follow your specialist’s exact instructions — and never stop blood thinners on your own.
2. Tamsulosin and the Risk of Floppy Iris Syndrome
Tamsulosin (Flomax) and related alpha-blockers are used for men with benign prostatic hyperplasia (BPH). However, they’re notorious in ophthalmology for increasing the risk of a complication known as Intraoperative Floppy Iris Syndrome (IFIS). This condition can make the iris behave unpredictably during surgery, potentially increasing surgical difficulty and prolonging the operation.
Even if you stopped taking tamsulosin months ago, its effects can linger in the eye. That means your surgeon needs to know if you’ve ever taken it — not just whether you’re currently on it. Sometimes stopping the drug isn’t even helpful, so the more important step is for your eye surgeon to prepare with special techniques and devices to protect the iris. Disclosure is the key, not necessarily discontinuation.
3. Diabetes Medications: Timing and Adjustments
Diabetics often need special planning for surgery, particularly around managing blood glucose on the day. If you take oral drugs like metformin or insulin injections, your surgical team will guide you on what to take or skip. Why? Because you’ll likely be fasting beforehand, and taking your usual dose of insulin or tablets could cause a dangerous drop in blood sugar.
Some guidelines recommend skipping the morning dose of oral hypoglycaemics on surgery day. Insulin doses may be reduced or adjusted to avoid hypoglycaemia. Metformin, in particular, may be withheld around the time of surgery to reduce the rare risk of lactic acidosis, especially if any IV contrast is being used or kidney function is borderline. Don’t make any changes on your own — your surgeon or anaesthetist will give you specific instructions in advance.
4. Herbal Supplements: Natural Doesn’t Always Mean Safe
It might seem harmless to pop a few herbal supplements before surgery, but many of these can interact with medications, thin the blood, or increase the risk of anaesthetic complications. Common culprits include ginkgo biloba, garlic tablets, ginseng, St John’s Wort, turmeric, and even fish oil. These substances can prolong bleeding time or affect clotting mechanisms.
In general, most surgeons advise stopping all herbal supplements 1–2 weeks before cataract surgery. This isn’t because they’re inherently dangerous, but because they introduce unknown variables in the perioperative period. Always mention any supplements — even if they’re over-the-counter or labelled as “natural.”
5. Antidepressants and Antipsychotics: Caution Around Intraocular Pressure
Certain psychiatric medications — particularly tricyclic antidepressants, SSRIs, and antipsychotics — may influence intraocular pressure or have interactions with anaesthetic agents. While these drugs are rarely stopped outright for cataract surgery, they are still worth discussing.
For example, tricyclics can potentially affect pupil dilation during the operation. SSRIs, on the other hand, might increase bleeding risk slightly. What matters most is that your surgeon knows about them — not just for surgical planning, but also to help reduce any anxiety about the procedure with safe supportive strategies.
6. Anti-inflammatory Drugs: NSAIDs and Steroids
Non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen, diclofenac, and naproxen have mild blood-thinning effects and may increase the risk of periocular bruising or bleeding. In general, surgeons don’t always ask for them to be stopped, especially if you’re on them for chronic pain or arthritis. However, timing and dose adjustments might be considered depending on your risk profile.
Systemic steroids like prednisolone present a different challenge. These can affect wound healing, immune function, and blood sugar levels. If you’re on long-term steroids, your surgeon may liaise with your GP or specialist to determine whether any changes are needed before surgery. If you’ve been on steroids for more than a few weeks, you might also need steroid cover during the procedure.
7. Antihypertensives: To Stop or Not to Stop?
Blood pressure tablets — like ACE inhibitors, beta-blockers, calcium channel blockers, or diuretics — are usually continued through cataract surgery. In fact, maintaining good blood pressure control is crucial for a smooth and uneventful operation.
That said, certain blood pressure meds, like ACE inhibitors or diuretics, might make you feel dizzy if you’re fasting or dehydrated on the day of surgery. Some surgeons may advise skipping the morning dose, especially if you’re prone to postural hypotension. Again, don’t guess — ask your surgeon or anaesthetist what they recommend based on your specific medications and general health.
8. Antiepileptics: Stability Is Key
If you’re on antiepileptic drugs like carbamazepine, valproate, lamotrigine or levetiracetam, the last thing you want is a missed dose triggering a seizure. These medications are almost always continued throughout the surgical period. Your medical team may help adjust the timing if you’re fasting but will aim to maintain therapeutic levels.
Importantly, make sure your surgical team knows about your seizure history and medication list. Even if cataract surgery is local rather than general anaesthetic, stress or sleep disruption can sometimes lower your seizure threshold, so careful planning is needed.
9. Eye Drops: Which Ones Stay, and Which Ones Go?
If you’re already on prescription eye drops — whether for glaucoma, dry eye, allergies, or previous infections — your ophthalmologist will give you instructions on which to continue and which to stop. Glaucoma drops, for example, are typically continued right up to and after surgery to control intraocular pressure.
Some medicated drops, like steroid or antibiotic drops started before surgery, will be managed as part of your surgical plan. If you’re using anything bought over-the-counter, let your surgeon know — even things like redness-relieving drops or lubricants, as some formulations might interfere with surgical preparations.
10. Immunosuppressants and Biologics: Special Consideration Required
For patients on immunosuppressive therapy due to autoimmune conditions, organ transplants, or cancer treatment, cataract surgery requires extra coordination. Drugs like methotrexate, mycophenolate, azathioprine, or biologics like adalimumab or infliximab may suppress healing or elevate infection risk.
Sometimes these medications are paused temporarily, depending on your underlying condition and your physician’s input. In other cases, it may be safer to continue them but take extra steps to protect against infection. The timing of your surgery may also be scheduled around your medication cycle to reduce immune suppression at the peak healing time.
Frequently Asked Questions
- Should I stop aspirin before cataract surgery?
Whether or not you should stop aspirin depends largely on why you’re taking it. If it’s part of your treatment plan following a heart attack, stroke, or stent placement, your surgeon may recommend continuing it to avoid any risk of clotting. However, if you’re taking aspirin for general cardiovascular protection or without a clear medical indication, your surgical team might advise stopping it a few days prior to surgery to minimise the risk of bleeding during anaesthetic injection or surgery itself. This decision should always be made in coordination with your GP, cardiologist, and cataract surgeon. - Can I take metformin on the day of my cataract surgery?
Most patients are advised not to take metformin on the morning of cataract surgery, especially if they are fasting or expected to receive intravenous contrast or sedation. Metformin carries a rare but serious risk of lactic acidosis, particularly in patients with compromised kidney function or those who become dehydrated. Skipping the morning dose under medical advice helps to mitigate this risk while ensuring your blood sugar remains safely controlled through other means. Your surgical team will give you clear instructions based on your diabetes management plan. - Do herbal supplements like turmeric need to be stopped before cataract surgery?
Yes, it’s generally recommended to stop herbal supplements — including turmeric, ginkgo biloba, garlic, and ginseng — at least one to two weeks before cataract surgery. Despite being natural, many of these supplements have blood-thinning properties that can increase your risk of bleeding or bruising during the operation. Some can also interfere with anaesthesia or interact unpredictably with prescription medications. It’s important to let your surgical team know about any herbal or over-the-counter supplements you’re taking so they can advise you safely. - What happens if I forget to tell my surgeon about a medication?
Forgetting to mention a medication could pose serious risks, as even seemingly unrelated drugs can affect anaesthesia, bleeding, healing, or intraocular pressure. For example, tamsulosin used for prostate issues can cause floppy iris syndrome during surgery, while blood thinners could increase bleeding risk. Always bring a full, up-to-date list of your medications, including prescription tablets, eye drops, and over-the-counter products, to your preoperative assessment. Complete transparency ensures your surgeon can plan effectively and avoid complications. - Can I keep using my glaucoma drops before surgery?
In most cases, glaucoma drops should be continued before cataract surgery to keep intraocular pressure under control. These medications play a vital role in preventing optic nerve damage and preserving your vision. However, depending on the type of drop and timing of your surgery, your ophthalmologist may make adjustments to the schedule or temporarily switch to a different formulation. It’s important not to stop these drops on your own — always follow your surgeon’s guidance on how to manage them before and after the procedure. - Is it safe to continue blood pressure tablets before surgery?
Many blood pressure medications can be continued before cataract surgery, but there are exceptions based on your risk of low blood pressure during fasting. Some surgeons may advise you to skip your morning dose of certain medications, especially diuretics or ACE inhibitors, if you are at risk of dizziness or hypotension. Maintaining stable blood pressure is important for surgical safety, so the decision will depend on your general health, type of anaesthesia used, and whether you’re prone to postural drops in pressure. Always check with your surgical team beforehand. - Should tamsulosin be stopped before cataract surgery?
Tamsulosin and similar alpha-blockers can cause a condition called intraoperative floppy iris syndrome (IFIS), which can make the pupil behave unpredictably during surgery. However, even stopping tamsulosin before surgery doesn’t always eliminate the risk, as its effects may persist for months. The most important thing is to inform your surgeon if you are currently taking or have ever taken this medication. With that knowledge, your surgeon can use specialised techniques and tools to manage the iris safely during your procedure. - Can antidepressants cause problems during cataract surgery?
Antidepressants, particularly SSRIs and tricyclics, can have minor effects on bleeding tendency or pupil size, but they are not typically stopped before cataract surgery. Stopping these medications abruptly can lead to withdrawal symptoms, mood instability, or relapse of depression or anxiety. Instead, your surgeon simply needs to know about them in advance so they can take any necessary precautions with anaesthesia and surgical planning. Maintaining mental health stability around the time of surgery is important, so continue your medications unless explicitly told otherwise. - Will I need to stop immunosuppressants before cataract surgery?
Whether or not you stop immunosuppressive medication depends on the underlying condition being treated and your overall immune status. In patients with autoimmune diseases or those who have had organ transplants, drugs like methotrexate or biologics may be paused temporarily to reduce infection risk and support wound healing. However, this must be carefully balanced against the risk of disease flare or transplant rejection. Your surgeon will coordinate closely with your specialist to determine the safest course of action based on your specific needs. - What if I’m on multiple medications — how do I keep track?
If you’re on several medications, the best approach is to maintain a written list that includes the name of each drug, its dose, the time you take it, and the reason it’s prescribed. This should include tablets, eye drops, inhalers, injections, and any over-the-counter or herbal products. Bring this list with you to every medical appointment, and update it whenever your prescriptions change. Doing this helps ensure your care team can make safe decisions before, during, and after cataract surgery and helps prevent harmful drug interactions.
Final Thoughts
Cataract surgery is one of the safest procedures performed today, but a lot of that safety comes from careful planning — and that includes your medications. What you take daily can affect your risk of bleeding, infection, intraoperative complications, and post-op healing. So don’t hold anything back. Bring a full list to your pre-op appointment, including prescription meds, over-the-counter products, eye drops, and supplements. It may seem like a lot of fuss, but your surgical team really needs that full picture to protect your health.
At London Cataract Centre, we work closely with your GP and other specialists to ensure your procedure goes smoothly. Whether you’re managing diabetes, heart disease, or anything else, we take a personalised approach to medication safety — so you’re fully prepared and in safe hands.
References
- Kara‑Junior, N., Santhiago, M.R., Espindola, R.F. and Arieta, C.E., 2018. Anticoagulants and antiplatelet drugs during cataract surgery. Arquivos Brasileiros de Oftalmologia, 81(4), pp.348–353.
Available at: https://pubmed.ncbi.nlm.nih.gov/29995131/ - Chang, D.F. and Campbell, J.R., 2005. Intraoperative floppy iris syndrome associated with tamsulosin. Journal of Cataract & Refractive Surgery, 31(4), pp.664–673.
Available at: https://pubmed.ncbi.nlm.nih.gov/15878464/ - Patel, R. and De Klerk, T., 2019. Novel oral anticoagulants in cataract surgery—moving towards a national consensus regarding perioperative continuation. Eye, 33, pp.1820–1823.
Available at: https://www.nature.com/articles/s41433-019-0527-7 - Fung, A.T. and McCluskey, P., 2010. Tamsulosin-induced intraoperative floppy iris syndrome during cataract surgery. Australian Prescriber, 33(6), pp.179–181.
Available at: https://www.nps.org.au/australian-prescriber/articles/tamsulosin-induced-intraoperative-floppy-iris-syndrome-during-cataract-surgery - Corliss, J., 2017. Taking an anticlotting drug? If you need a procedure, be prepared. Harvard Health Publishing, Harvard Medical School.
Available at: https://www.health.harvard.edu/blog/anticlotting-drug-procedure-safety-2017110112659