In the name of Allah, most gracious , most merciful
In general, the scholars mention that there are three ways to prevent and remove illnesses and troubles from one: medical means, dua, and amulets (ta`wiz) for protection. One should always do the former two (take medical means, and turn to Allah in dua) and use the third (ta`wizes) when the need is felt for them.
One of the most important Qur'anic duas for protection against magic is to recite the Two Surah of Protection (al-Mu’awwadhtayn), namely, Surah Al Nas and Surah Al-Falaq.
Ka`b Ahbar (Allah be pleased with him) says, "If I had not read few words, then the Jews would have made me into a monkey."
Someone enquired, what are they?
He said the following:
A’udhu biwajhi hil’adhim alladhi laysa shay’un a’dhmu minhu,wa bikalimatillahi’l tammati’l lati la yujawizuhunna barrun wala fajirun wabi’l asma’illahi’l-Husna ma’ alimtu minha wa malam a’lam min sharri ma khalaq wizran wa birran. ['I seek refuge in the Countenance of Allah, which nothing is more tremendous than, and in His most perfect words which not righteous or sinful man can excel, an in His most beautiful Names, the ones I know and the ones I know not, from the evil of His creation, whether good or bad.']
One should recite this dua morning and afternoon three times. (Reported by Imam Malik)
One should make the following dua if one has hurt another:
The Prophet (Allah bless him and give him peace) use to make the following dua:
Allahumma fa’ayyuma mumim sababna aw la’anna faj’al dhalika lahu qurbatan ilaka yawmal qiyam. ['O Allah, any believer we insulted or cursed, make that a way for them to gain closeness to You on the Day of Resurrection.']
There are numerous duas from our Beloved Prophet (Allah bless him and give him peace) and the companions and those who came after them.
(F: We should get a good book of duas, and 'live' the supplications of the Prophet through continual recital of them in all our affairs. Also, see the related post on 'Effective Ta`wizes')