The story is, sadly, true. The Government owe the Chemists about 80 million Euros for the supply of drugs..... Whether that will affect you, since you presumably by the items you need over the counter is another matter. The main effect at the moment is for drugs prescribed by your local (Canarian) GP.
If it is likely to be a major problem for you, make sure you bring some extra's with you - there is little chance of the situation improving any time soon - Spain is broke.