Participants FAQs About GaPP2

Chronic pelvic pain (CPP) affects over 1 million women in the UK. The reason why women suffer from CPP is poorly understood. In as many as half of the women with CPP, no cause can be found. The management of CPP is therefore difficult.

In this study we will use a drug called gabapentin. Gabapentin is a commonly used drug for other chronic or long term pain conditions but there is no proof that it helps women with CPP. We carried out a small study comparing gabapentin against placebo (an identical dummy capsule) and this showed that it might help with this pain but we need more evidence, therefore we are asking you to take part in this larger study to try and prove whether it works.

We will give half the women in our study gabapentin and half a placebo for sixteen weeks. You will not know whether you are taking gabapentin or placebo until the end of the study. We will ask you to tell us how your pain is at the beginning of the study before you take any capsules and again for the last 4 

No - taking part is completely voluntary. If you do decide to take part, you can withdraw from the trial at any time, without providing a reason. This will not affect your care in any way.

You will be asked to sign a consent form by a member of the research team. We will then ask you some questions to make sure that it is safe for you to take part in the trial and this will include questions about your medical history and any medications you are on.

Once we know it is safe for you to take part we will ask you over the next four weeks to text or phone us with your average and worst pain score for each week. This will be a quick message asking you to tell us a number between 0 and 10 describing your worst and average pain. Once we have this information, we can see if you can take part in the study. 

If you are not eligible to take part, you will not be randomised to any treatment and your care will return to your usual doctor.

If you are eligible to take part, you will be asked to come into the hospital for a visit to fill in some questionnaires. Some of the questions are of a sensitive nature (for example, about your pain and sexual history) but you will complete them in private and they will not contain any information that can identify you. 

We will carry out a pregnancy test to ensure it is safe for you to take the study medication and if negative you will be given, at random, either gabapentin or placebo capsules. These capsules look exactly the same so nobody will know which treatment you are on. You will also be given a diary and shown how to fill this out. This will need to be completed every day.

This is important as it will tell how much of the study drug you have taken and also what other medication you may take to help with your pain. Filling out the diary will take about five minutes at the end of each day. This can either be on paper form or over the internet. We will send you a brief text message or phone you every week to remind you complete this.

It is important that you do not get pregnant while taking this drug so we will ask you to use effective contraception (if necessary) for the time you are in the trial.

For the first few weeks, we will get you will increase the dose of the capsules that you take each day – instructions will be given to you and you can contact the trial team at any

time for help with this. Once you are at the dose that gives you the best pain relief with no or few acceptable side effects, you will stay on this dose for the next 12 weeks. You may have to come into the hospital about half way through the study for a short visit with the research nurse to pick up some more medication. 

For the last 4 weeks we will ask you to text or phone us to tell us your pain scores again each week. At the end of the 12 weeks you will come into the hospital for another visit with the research nurse to hand in your unused drugs and your diary, and to complete some questionnaires again. 

At this visit you will be told what drug you were taking, e.g. gabapentin or placebo. You will then have the opportunity to continue or start on gabapentin (if on placebo) if you wish. Please see page 4 for full details of what will happen during the study. 

Reasonable travel expenses will be reimbursed for all research visits.

You may or may not get a direct benefit from taking part in this trial. It is hoped that the findings will demonstrate that gabapentin is a safe, acceptable and effective treatment for chronic pelvic pain.

You will have a 50% chance of getting gabapentin which is a drug commonly used for pain although we don’t know if it works for chronic pelvic pain.

Gabapentin is not a new drug and is a drug widely used for the treatment of pain. It is a strong painkiller and can be safely taken by most people but, as with every drug, some people can suffer side effects.

The most common side effects from gabapentin include drowsiness, dizziness, fatigue, fever, increased infections/risk of infections, a change in appetite (may increase or decrease), changes in blood pressure, visual disturbances, changes to your skin (including rash or swelling) pain (including joint/muscle or abdominal), respiratory conditions (including shortness of breath), digestive/urinary disturbance and a change in mood (including feeling anxious or depressed).

You may feel drowsy so it is advised not to drive or operate machinery until you know that you feel you are safe to do so. If you do suffer from any side effects reducing the dose or stopping the capsules stop these. It is not known if gabapentin is of any risk to pregnant women, so we will ask you to not get pregnant during the course of the study. We will ask you what contraception you are using, if necessary at each visit.

Yes. All information which is collected about you during the course of the research will be kept strictly confidential. You will be allocated a unique code and your responses to the questions will be held in a coded form in a secure central database which is only accessible to the research team. Your responses will not be identified when the results of the study are published. However, we do ask permission to contact your GP to let them know that you are taking part in the study.

The research is being organised by Prof Andrew Horne (Consultant Gynaecologist), University of Edinburgh and funded by National Institute for Health Research. This trial is jointly sponsored by the University of Edinburgh and NHS Lothian. It is being run with support from Birmingham Clinical Trials Unit.

This study has been given a favourable ethical opinion for conduct in the NHS by the National Research Ethics Committee – Coventry and Warwickshire.

If you have a concern about any aspect of this study, you should ask to speak with the clinical researchers who will do their best to answer your questions. If you remain unhappy and wish to complain formally, you can do so through the NHS Complaints Procedure. Details can be found at the end of this leaflet.

The results of this study will be published e.g. in medical journals, reports and textbooks. The anonymised data will be stored for five years at the University of Edinburgh and may be considered for possible use in future ethically approved projects.