If you have hemorrhoids, you should find a stool softener that you can take on a regular basis. Overexerting yourself when pushing out a bowel movement will create a lot of pain for you, and perhaps make yourself more vulnerable to future problems.
Never rely on laxatives as a method of remedying hemorrhoids, as they are not meant to be taken on an ongoing basis. While it is acceptable to use laxatives periodically for relief of constipation, taking them does little to prevent hemorrhoids from forming.
When your hemorrhoids itch, it is sometimes tempting to scratch them. No matter how much you want to scratch, you should resist the temptation in order to avoid opening the hemorrhoid. If they get opened for any reason, they will be far more painful and susceptible to bacterial infection.