Alpharma Sells Generic of Pfizer Drug  NEW YORK (Reuters) - Alpharma Inc. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=ALO.N target=/stocks/quickinfo/fullquote"&gt;ALO.N&lt;/A&gt; on Friday began  selling a cheaper generic version of Pfizer Inc.'s &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=PFE.N target=/stocks/quickinfo/fullquote"&gt;PFE.N&lt;/A&gt;  epilepsy drug Neurontin without waiting for a court ruling on  Pfizer's request to block the copycat medicine.