About diltiazem Who can and cannot take it How and when to take it Side effects Pregnancy, breastfeeding and fertility Taking it with other medicines and herbal supplements Common questions Related conditions Anal fissure Angina High blood pressure (hypertension) Coronary heart disease Heart attack Stroke Raynaud's phenomenon Useful resources Blood Pressure UK: Charity www.bloodpressureuk.org British Heart Foundation: charity www.bhf.org.uk NHS Health Check