You can make homemade honey syrup to relieve the cough. You require lemon juice, warm water and honey. Mix all these ingredients and stir slowly until they are thoroughly mixed. Take two teaspoons of this mixture after every two hours to relieve and even stop the cough. It is important to seek medical attention if the cough persists.
Dissolve 1-2 tsp of dark honey in 2-4 oz of nicely warm water. Take a tsp or 2 as needed for cough. Sometimes a cough can be caused by post-nasal drip. If you have this you might try Sudafed (the kind you buy behind any pharmacy counter - NOT in the aisle). If the cough causes more than streaks of bleeding - or if you just can't make it stop it's time to see a doctor.
An old remedy: butter, lemon juice and sugar. Put about 1/2 pat of butter on the end of the spoon. Then fill the bowl of the spoon with sugar. Keep dry until ready to use. When ready to use, put enough lemon juice on the sugar to saturate it. Put the spoon in your mouth all at once and mix in your mouth before swallowing. This worked for my husband when, as a boy, he had whooping cough. When the coughing spasms would come on, his father would give him this remedy and it would work for about an hour. A good rule of thumb; if this has lasted more than a week it's time to see a doctor.
Oh: White Horehound herb is specific for calming down the urge to cough. No side effects, VERY effective. They used to make candy with Horehound in it - can you still get that? Try making a tea from White Horehound (third of a cup of chopped herb, top up with boiling water) and honey to taste. Cool and sip as required. The other source is to phone a local Herbalist and get some Marrubium vulgare extract. Seriously: this stuff is MAGIC!!!
What always works for me, and my kids 100% of the time, as far as coughs, is the humidifier. I use the Vick's one with the hot steam and vapo steam. I wish I would've discovered it when I was a kid, or my parents anyway.