You could try Guaifenesin or Robitussin which is found in cough medicines. For either to be effective you need to know when you're approaching ovulation to take advantage of the use of either medicine as they work best on women who produce at least some CM. The only way to know that is by checking your CM. If you buy the liquid form of Guaifenesin, take two teaspoons three times a day around the time of month you're expecting to ovulate. In any form it is encouraged that you to take it from the first day you notice any type of wetness until the day of your change in body temperature. That may be for about a week.
When buying, you need to look for one in which Guaifenesin or Robitussin is the only active ingredient. Many cough and cold medicines contain antihistamines that also work systemically in your body but have the reverse effect. They dry up mucus and diminish wet cervical fluid. And while you're trying to get pregnant, you shouldn't expose yourself to any other drugs unnecessarily, so find a product that contains only guaifenesin and no other active ingredients, including dextromethorphan (a cough suppressant) and alcohol.
