My gums have grown since I started a blood pressure or epilepsy medicine: what should I do?

Drug-induced gum overgrowth comes from a build-up of the structural fibre called collagen in the connective tissue of the gum. In medical language it is called 'drug-induced gingival overgrowth' or 'gingival hyperplasia'. It is not a tumour or an infection; it is a side reaction of the tissue to a medicine.

Three groups of medicines stand out. The first is calcium channel blockers: nifedipine, amlodipine, diltiazem, verapamil and felodipine, used for blood pressure and chest pain (angina), belong to this group. The second is the epilepsy medicine phenytoin. The third is ciclosporin, used after organ transplants and in some immune diseases. Tacrolimus, from the same group, can also cause growth, but more rarely and more mildly.

The mechanism is not fully understood; one review proposes a common explanation for all of these medicines, but this has not yet been proven, it is a hypothesis. All of these medicines affect the passage of ions across the cell membrane. Less folic acid gets into the gum cells, and the enzyme that breaks down collagen is not activated enough. As a result, the tissue keeps making collagen but cannot break down the old; the gum thickens.

It does not happen to everyone. Of two people taking the same medicine at the same dose, one may find their gums growing while the other sees no change at all. The risk factors listed in reviews are: genetic predisposition, male sex, young age, a high dose, taking more than one trigger medicine together and, most important of all, bacterial plaque on the tooth surface and gum inflammation. Plaque is the factor with the biggest share in both the start and the severity of the growth, and it is the one you can change.

How often it happens varies a great deal from study to study. One review reports growth in about half of people taking phenytoin, nifedipine and ciclosporin; the range given for calcium channel blockers in general is 10 to 20 per cent, and for nifedipine 15 to 85 per cent. In a study carried out in Turkey among 131 patients who had been taking blood pressure medicine for at least two years, growth was seen in 31.8 per cent of the amlodipine group, 13.3 per cent of the lercanidipine group and 7.1 per cent of the benidipine group. In the same study, the overall difference between the medicine groups was not statistically significant, while a link was found between the amlodipine dose and growth. These numbers are small and come from different groups; they do not show your own risk, but they do show that the problem is not rare.

In people who have had an organ transplant, two groups can come together: ciclosporin, and a calcium channel blocker for blood pressure. One review reports that this combination roughly doubles the risk of growth compared with ciclosporin alone (51.9 per cent versus 25 per cent).

The growth does not cause pain by itself, but it has consequences. The thickened gum creates a false pocket on the surface of the tooth; the brush cannot reach it, plaque builds up, and the inflammation makes the growth even worse. In advanced cases, speaking, chewing and keeping the mouth clean become harder; reviews report cases going as far as pain and tooth loss.

The dentist makes the definite distinction by examination and, if needed, a tissue sample. The signs below help you understand which way to look. If a sign in the second list applies, do not wait.

Treating drug-induced growth needs two doctors working together: the dentist and the doctor who prescribed the medicine (cardiologist, neurologist, nephrologist or transplant team). The sequence below is built to get the most result with the least intervention.

1. 1

   Take a complete list of your medicines

   Write down the name and dose of every medicine you take, and add how long you have been taking it. Blood pressure medicines, epilepsy medicines, transplant medicines and diuretics (water tablets) are especially important. How long after starting the medicine the growth was noticed helps with the diagnosis.

2. 2

   Dental examination and ruling out other causes

   The dentist looks at the spread, colour and consistency of the growth; measures pocket depth and takes an X-ray if needed. If there is atypical tissue, on one side only or growing fast, a sample may be taken. If a blood disorder is suspected, a blood count is requested.

3. 3

   Plaque and tartar cleaning

   The first and most effective step of treatment. Tartar and plaque are cleaned off, going down into the pocket if needed. Because part of the growth comes from inflammation, the tissue noticeably thins with this step alone. Brushing and cleaning between the teeth are shown to you at this stage.

4. 4

   A talk with the doctor who prescribed the medicine

   Get a short note from your dentist: ask them to write which medicine is suspected and how severe the growth is. Your doctor may consider switching to an option that serves the same purpose with a lower tendency to cause growth, or reducing the dose. This decision is entirely theirs; the risk to blood pressure, of seizures or of organ rejection comes before the gums.

5. 5

   Follow-up after the change

   One review states that when the medicine is changed and plaque is brought under control, full resolution can be expected within 1 to 8 weeks. In a small series of four patients switched from ciclosporin to tacrolimus, there was marked improvement in all four, but full resolution was seen in only one. So a change is often enough, but not always.

6. 6

   Surgery for the remaining tissue

   If, after cleaning and a change of medicine, there is still excess tissue that gets in the way of cleaning or spoils the appearance, gum trimming (gingivectomy) or flap surgery is carried out. In people who stay on the medicine, the growth can come back after surgery; that is why surgery is usually the last step.

These options do not compete with each other; they are usually used in sequence. Where to stop is decided by how severe the growth is and whether the medicine can be changed.

With drug-induced growth, the most costly mistakes come from decisions about the medicine being made by the wrong person.

The sequence below is a general framework for a route that starts with cleaning and, if needed, extends to a change of medicine and surgery. Timings vary from person to person.

1. The days after cleaning

   The gums may be tender, and bleeding when you brush may seem to increase in the first few days. As the inflamed tissue starts to thin, the bleeding decreases.

2. The first weeks

   The part of the growth caused by inflammation goes down and the gum firms up. The fibrous part, meaning the hard, stringy part, hardly changes with cleaning. Growth caused by phenytoin and nifedipine tends to be more fibrous, while growth caused by ciclosporin tends to be more inflamed.

3. 1–8 weeks after a change of medicine

   If your doctor has changed the medicine and plaque control is good, marked improvement is expected in this period. The improvement may stay slow or partial.

4. Healing after surgery

   If trimming has been done, the surface closes over within a few weeks. If the medicine continues, regular check-ups from this point on are the only way to catch a recurrence early.

There is no single procedure for drug-induced growth; the scope changes with the factors below.

How widespread the growth is

Growth limited to between a few teeth and growth covering both jaws entirely do not call for the same treatment.

The amount of inflammation and tartar

As tartar and pocket depth increase, cleaning spreads over more than one session and cleaning inside the pockets.

Whether the medicine can be changed

If the medicine can be changed, surgery is often not needed; if it cannot, more frequent maintenance and repeated procedures come into the calculation.

Whether surgery is needed, and the method

Scalpel, laser or flap surgery; how many areas will be treated and how many sessions it is split into determine the scope.