Methods and compositions for protecting and treating muscarinic receptors by administering a pyrophosphate analog to a subject exposed to bacterial, fungal, viral, prion or algal infection

A method of treating muscarinic receptors in a subject having a CNS infection, the CNS infection comprising meningitis wherein the CNS infection affects the subject's muscarinic receptors, comprising delivering an effective amount of pamidronate or a pharmaceutically acceptable salt thereof directly to the CNS of the subject and bypassing the blood-brain barrier by intranasally administering to the upper one-third of the subject's nasal cavity the effective amount of pamidronate of a pharmaceutically acceptable salt thereof;

• and
• treating the subject's muscarinic receptors that are affected by the CNS infection comprising meningitis.