Brief Answer:
Information

Detailed Answer:
Hello and welcome,

I see that you live in the northern U.S. so I won't be considering any exotic type of infections.

Coughs, with no history of asthma or respiratory diseases, and no history of inhaled irritants, are usually due to infection or allergies. Right now Birch tree pollen is very high. With allergies, there can be drainage down the back of your throat that can cause an irritating cough. That can also happen with an upper respiratory infection such as a cold. Infections can sometimes start in the lungs (pneumonia) but then you would feel quite ill with a fever so this is unlikely.

So my best guess is that it is drainage from the sinuses that is causing the cough. Without examining you it is hard to know for sure, but I am basing it on what you wrote and what is most common.

The metallic or blood taste may be from a small amount of blood from a broken capillary. When there is a lot of coughing, a tiny blood vessel can break. This is not serious. We get concerned if you are coughing up large amounts of blood of course, but it is likely to be quite small if you are only tasting it and not seeing it.

If you are not feeling otherwise poorly, here are some suggestions of what you might do:

Dextromethorphan: this is an over the counter cough suppressant. Some people find it helpful, others don't.

Saline sinus irrigation: if the problem is coming from drainage down the posterior pharynx, irrigating your sinuses, either with a Netipot, or prepared saline spray, may help to reduce this.

Antihistamine: you can try a Zyrtec, Claritin, or Allegra and see if in a few hours it makes a difference in the coughing.

Steroid nasal spray: Flonase is an example and is sold over the counter. This can help stabilize the membranes of the nose and sinuses, and thereby decrease the problem. It can take a day or two to start to see results.

I hope this information helps. Please let me know if I can provide further information.

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