Attention: Blood Sugar Problems Do Not Wait

As a doctor working in Australia, I see it every week: people over 30 who are tired, gaining weight around the middle, craving sugar after meals, and getting blurry vision or pins and needles. Many have been told their blood glucose is “a little high” or they have “pre‑diabetes.” Others already have type 2 diabetes and feel overwhelmed by the diagnosis. If that sounds familiar, you are not alone. More than 1.3 million Australians live with diabetes, and many more have prediabetes without knowing it.

The pain points are real: low energy, fear of needles, confusion about medication, worry about side effects, and rising pharmacy costs. The good news is that one medicine has stood the test of time for over 60 years and is still the first choice for most people: metformin.

In this review, I want to answer the questions my patients actually ask me about metformin. I will cover thyroid function, alternatives if it upsets your stomach, nerve pain, hepatitis B and C, PBS costs, combination therapy, statins, and dialysis. By the end, I hope you will feel confident and ready to act.

Interest: Why Metformin Is Still My First Choice

Metformin is not a new flashy drug, and that is exactly why I trust it. It works by reducing the amount of glucose your liver makes, improving your body’s sensitivity to insulin, and slowing glucose absorption from the gut. It does not usually cause dangerous low blood sugar when used alone, and it does not cause weight gain — in fact, many people lose a little weight or stay weight neutral.

The Royal Australian College of General Practitioners and Diabetes Australia recommend metformin as first‑line therapy for type 2 diabetes unless there is a specific reason not to use it. It is also used in polycystic ovary syndrome (PCOS) and sometimes to help prevent type 2 diabetes in high‑risk people.

I often tell my patients that metformin is like a reliable teammate. It does not do all the work, but it makes every healthy change you make — eating well, walking more, losing a few kilos — work much better.

Desire: Answering Your Real Questions

Below are the specific concerns my patients raise in the consultation room. I have answered them from an Australian doctor’s perspective, using plain language.

1. Does Metformin Affect Thyroid Function?

This is a common question, especially for people taking thyroxine for an underactive thyroid. The short answer is: metformin can slightly lower thyroid‑stimulating hormone (TSH) levels, but it does not usually cause thyroid disease or make your thyroid function abnormal in a harmful way. In people with hypothyroidism on levothyroxine, metformin may reduce TSH a little, which sometimes leads to a dose adjustment of thyroxine.

In my practice, I check thyroid function before starting metformin if a patient has known thyroid disease or symptoms such as fatigue, weight changes, or feeling cold. After starting, I recheck TSH if there is any concern. For most people with a normal thyroid, metformin is safe and does not cause thyroid failure.

Bottom line: Metformin may shift your TSH slightly, but it is not a reason to avoid the drug. If you take thyroid medication, your doctor can monitor your levels and adjust if needed.

2. What Are the Alternatives to Metformin If Not Tolerated?

The most common reason people stop metformin is stomach upset. Before giving up, I always recommend:

• Starting with a low dose (e.g., 500 mg once daily).
• Taking it with or immediately after food.
• Switching to extended‑release (XR) metformin, which is gentler on the gut.

If these steps fail and metformin truly cannot be tolerated, there are several good alternatives in Australia. The table below summarises them.

In many cases, these alternatives can be used alone or in combination with metformin. But remember: metformin usually remains the backbone of treatment because of its safety, low cost, and long‑term evidence.

3. Metformin and Neuropathy: Does It Help?

Diabetic neuropathy — tingling, numbness, burning or pain in the feet and hands — is one of the most feared complications of high blood sugar. Does metformin help? The honest answer is that metformin does not directly repair nerve damage or treat neuropathic pain. However, by lowering blood glucose, it helps prevent further damage to nerves and small blood vessels.

There is one very important catch: long‑term metformin use can lower vitamin B12 levels in up to 30% of people, and low B12 can itself cause or worsen neuropathy. In Australia, I recommend checking vitamin B12 levels at baseline and then every 1–2 years, especially if you are over 60, vegetarian, vegan, or have had stomach surgery. If B12 is low, simple supplementation can make a big difference.

Bottom line: Metformin helps control glucose, which protects nerves over time, but it does not treat existing neuropathy. Ask your doctor to check your B12 if you have nerve symptoms while taking metformin.

4. Metformin and Hepatitis B/C Considerations

Many Australians live with chronic hepatitis B or C, and type 2 diabetes is common in this group. The old fear was that metformin could cause lactic acidosis in people with liver disease. Modern evidence shows that metformin is safe in mild to moderate, stable chronic liver disease, including well‑managed hepatitis B and C, as long as liver function tests are reasonable and there is no decompensated cirrhosis.

If you have hepatitis B, continue your antiviral medicine and have regular monitoring. If you have hepatitis C, modern treatments can cure it, and metformin can usually be continued during and after treatment. I avoid metformin only if there is severe liver failure, ascites, jaundice, or a recent flare of hepatitis with very high liver enzymes.

Bottom line: For most people with hepatitis B or C and controlled liver function, metformin is safe and can even improve fatty liver. Your doctor will monitor your liver and kidney function to keep you safe.

5. What Is the PBS Co‑payment for Metformin?

One of the best things about metformin in Australia is its price. Metformin is listed on the Pharmaceutical Benefits Scheme (PBS), which means the government subsidises it. The current PBS co‑payment amounts are shown below.

Because metformin is a very cheap medicine, many people actually pay less than the co‑payment — often only a few dollars for a box. Once you reach the PBS Safety Net threshold, your medicines become even cheaper or free. This makes metformin one of the most affordable diabetes medicines in Australia.

6. Metformin and SGLT2 Inhibitors Combination Therapy

In recent years, SGLT2 inhibitors like dapagliflozin and empagliflozin have become very popular because they protect the heart and kidneys. They work by making the kidneys remove extra glucose in the urine. In my practice, I often prescribe metformin and an SGLT2 inhibitor together because they complement each other beautifully.

• Better glucose control: Metformin reduces liver glucose output; SGLT2 inhibitors increase urinary glucose loss.
• Weight benefits: SGLT2 inhibitors cause some weight loss; metformin does not oppose this.
• Heart and kidney protection: SGLT2 inhibitors reduce heart failure and kidney disease progression.
• Low hypo risk: Neither usually causes dangerous hypos on its own.

The combination is generally safe, but you need to drink enough water, watch for genital thrush, and have your kidney function checked before starting and regularly afterwards. If you have type 2 diabetes with heart or kidney issues, ask your GP whether this combination is right for you.

7. Does Metformin Interact with Statins?

Many Australians over 50 take a statin to lower cholesterol, especially if they have diabetes or high cardiovascular risk. The good news is that metformin and statins do not have a significant interaction. They can be taken together safely, often at the same time of day.

Statins can occasionally raise blood glucose slightly in some people, but this is usually minor and does not outweigh the heart and stroke protection they provide. Metformin helps manage glucose and may even offset any small rise. I commonly prescribe both together, and I rarely see problems. Routine monitoring of diabetes control while on a statin is sensible.

8. Is Metformin Dialysable?

Yes, metformin is dialysable. This means that if someone develops metformin‑associated lactic acidosis — a very rare but serious complication — or takes an overdose, haemodialysis can be used to remove metformin from the blood and save lives. This is one reason hospitals manage these rare cases effectively.

In everyday practice, this fact matters because metformin must be stopped or reduced if your kidneys are not working well. In Australia, the general rules are:

• eGFR 45–59 mL/min: Continue metformin but review regularly.
• eGFR 30–44 mL/min: Reduce dose and monitor closely.
• eGFR <30 mL/min: Stop metformin, especially before dialysis or contrast scans.

If you have kidney disease, your doctor will check your kidney function regularly to keep you safe.

Action: Take Control of Your Health Today

Metformin is a proven, safe, and affordable medicine that has helped millions of Australians manage type 2 diabetes, prediabetes, and PCOS. If you are over 30 and struggling with high blood sugar, low energy, or weight gain, metformin could be an important part of your solution.

Here is what I want you to do next:

1. Book a GP appointment and ask for a diabetes check, including HbA1c, kidney function, liver function, and vitamin B12.
2. Discuss metformin with your GP. Ask about starting at a low dose and taking it with food to avoid stomach upset.
3. Ask for a PBS prescription so you pay no more than $31.60, and often much less.
4. Monitor your B12 and kidney function as recommended to stay safe long term.
5. Combine metformin with small lifestyle changes — a 20‑minute walk, fewer sugary drinks, and more vegetables. These changes work better with metformin on board.

Do not wait for the complications of high blood sugar to arrive. Metformin is not a miracle, but it is one of the best tools we have. Ask your doctor today whether it is right for you.

This article is for general information only and does not replace individual medical advice. Always consult your doctor before starting, stopping, or changing any medication.