The short answer
People with diabetes or high blood pressure have operations safely every day, but both need to be well controlled first. Poorly controlled sugar slows healing and raises the risk of wound infection, and very high blood pressure raises the risk of heart problems and stroke around the operation, so a planned operation may be postponed until they are better controlled. Your medicines usually change on the day before and the day of surgery, and only your doctor should decide how.
Book cataract surgery, from ₦420,000Medically reviewed by Dr Debo Odulana, Founder and Chief Executive, Mezo. Last reviewed . This page is general information, not a diagnosis. Care is decided with you after an examination.
Why control matters before an operation
An operation is a stress on the body. It pushes blood sugar and blood pressure up, and fasting can push sugar down. When diabetes is poorly controlled, wounds heal more slowly and infection is more likely. When blood pressure is very high, the risk of heart attack, stroke and bleeding rises. Getting both under control before a planned operation is one of the most useful things you can do.
This applies to planned operations. Emergencies go ahead with the team managing sugar and pressure as they go.
Diabetes: what will be checked
Your team will usually check your HbA1c, a blood test that shows your average sugar over the last two to three months, and your kidney function. If the HbA1c is high, your surgeon may advise a few weeks or months of better control before a planned operation. That delay can feel frustrating, but it lowers your risk.
- Bring your sugar readings from home, or a glucometer record
- Ask to be first on the morning list, so you fast for the shortest time
- Know the signs of low sugar: sweating, shaking, confusion, a racing heart. Tell staff at once
- Some diabetes tablets, including the newer ones ending in "-gliflozin", are usually stopped a few days before surgery
- Insulin doses usually change: you will be given a plan
High blood pressure: what to expect
Your blood pressure will be checked at your assessment and again on the day. If it is very high, a planned operation may be delayed until it is treated. Many people in Nigeria first learn they have high blood pressure at a pre-operative check. If that is you, it is a chance to start treatment that protects you for years, not only for the operation.
Most blood pressure tablets are taken as normal, including on the morning of surgery with a sip of water. Some, including certain water tablets and the "-pril" and "-sartan" families, are sometimes paused on the day. Your doctor will tell you which.
Do not stop your medicines on your own
Stopping blood pressure tablets suddenly can make your pressure rise sharply. Stopping diabetes medicines without a plan can push your sugar dangerously high. Stopping a blood thinner can cause a stroke or clot. Bring every medicine to your assessment, including herbal remedies, and follow the written plan you are given.
After the operation
Your sugar and pressure will be checked often while you are in hospital. Once you are eating normally, you usually go back to your usual medicines, but your doctor may change them for a few days. At home, check your sugar more often than usual for the first week, keep the wound clean and dry, and watch closely for signs of infection, because diabetes can hide them. Report any redness, discharge or fever early.
What it costs on Mezo
Standard monofocal lens, biometry and both post-operative reviews included.
Common questions
My sugar is high. Will they still operate?
For a planned operation, possibly not straight away. Your surgeon may ask you to improve control first, because high sugar raises the risk of infection and slow healing. For an emergency, the team manages your sugar during the operation.
Should I take my blood pressure tablet on the morning of surgery?
Most people take it as normal with a small sip of water, but some tablets are paused. Ask at your assessment and follow the written plan.
Can I have cataract surgery if I have diabetes?
Yes, people with diabetes commonly have cataract surgery, and good sugar control helps the eye heal. Cataract surgery on Mezo is from ₦420,000 per eye, with a written all-in quote after assessment.
Does diabetes stop a wound from healing?
Not usually, but healing can be slower and infection more likely, especially if sugar is poorly controlled. Keep your sugar steady and report early signs of infection.
I didn't know I had high blood pressure until the pre-op check. What now?
This is common. You will be advised on treatment and may need a short delay before a planned operation. Keep taking the treatment afterwards: it protects your heart, kidneys and brain long term.
The procedures
Related health guides
More patient guides
Sources and further reading
The guidelines and patient information this page is checked against. Care in Nigeria follows the same evidence; what differs is the price and where it is done.
- Perioperative care in adults. National Institute for Health and Care Excellence (NICE). Clinical guideline.
- High blood pressure. NHS. Patient information.
Links last checked 22 October 2026.
Medical disclaimer: This guide is general information and does not replace advice from your own doctor. Where your centre's instructions differ from this guide, follow theirs.