(P)
Palsy - Paralysis or uncontrolled movement of controlled muscles. It was listed as "Cause of death"
Paroxysm - Convulsion
Pemphigus - Skin disease of watery blisters
Pericarditis - Inflammation of heart
Peripneumonia - Inflammation of lungs
Peritonotis - Inflammation of abdominal area
Petechial Fever - Fever characterized by skin spotting Puerperal exhaustion - Death due to child birth
Phthiriasis - Lice infestation
Phthisis - Chronic wasting away or a name for tuberculosis
Plague - An acute febrile highly infectious disease with a high fatality rate
Pleurisy - Any pain in the chest area with each breath
Podagra - Gout
Poliomyelitis - PolioPotter's asthma - Fibroid pthisis
Pott's disease - Tuberculosis of spine
Puerperal exhaustion - Death due to childbirth
Puerperal fever - Elevated temperature after giving birth to an infant
Puking fever - Milk sickness
Putrid fever - Diphtheria.

(Q)
Quinsy - Tonsillitis.

(R)
Remitting fever - Malaria
Rheumatism - Any disorder associated with pain in joints
Rickets - Disease of skeletal system
Rose cold - Hay fever or nasal symptoms of an allergy
Rotanny fever - (Child's disease) ???
Rubeola - German measles